После осмотра меня ненадолго положили в палату, где уже спала маленькая девочка с мамой.

Because после requires the genitive case.

• осмотр = examination / check-up (dictionary form, nominative)
• после осмотра = after the examination

This is a very common pattern:

• после урока = after the lesson
• после работы = after work
• после ужина = after dinner

So осмотра is just the genitive singular form of осмотр.

Because меня is the direct object of положили.

Russian often uses an indefinite-personal construction where English would use the passive:

• Меня положили в палату
  literally: They put me in a ward
• natural English: I was placed / put in a ward

So:

• я = I (subject)
• меня = me (object, accusative/genitive form)

In this sentence, the speaker is not the grammatical subject. The implied subject is something like they — unnamed hospital staff, doctors, nurses, etc.

This is a very common Russian way to talk about actions done by unspecified people.

• положили = they put
• but it often really means someone put / they put / I was put

Russian often leaves the doer vague if it is obvious from context or unimportant.

Here, положили most likely refers to hospital staff, but the sentence does not name them because that is not the main point.

Compare:

• Меня спросили = They asked me / I was asked
• Его пригласили = They invited him / He was invited

So the plural here does not mean a specific known group is being emphasized. It is just a natural impersonal-style way to speak.

Yes, ненадолго is written as one word.

It means:

• for a short time
• briefly
• not for long

It is an adverb built from надолго (for a long time) with не-.

Compare:

• надолго = for a long time
• ненадолго = for a short time / not for long

So:

• меня ненадолго положили в палату
  = they put me in a ward for a short while

This is very natural Russian.

Because в палату expresses movement into a place, so Russian uses the accusative.

• в палату = into the ward / to the ward
• в палате = in the ward

This is the classic contrast:

• куда? (where to?) → accusative
• где? (where?) → prepositional

Examples:

• Меня положили в палату. = They put me into a ward.
• Я был в палате. = I was in the ward.

So here the action is directional: the speaker is being placed into the room.

In a hospital context, палата means ward or hospital room.

So в палату here is not just any room. It specifically means a patient room in a hospital.

Depending on context, English translations could be:

• ward
• hospital room
• room

Because где уже спала маленькая девочка с мамой is a subordinate clause describing палату.

So the structure is:

• в палату = into a ward
• где уже спала маленькая девочка с мамой = where a little girl with her mother was already sleeping

Russian normally separates this kind of clause with a comma.

You can think of it as:

• ...into a ward, where...

Yes. Here где literally means where and refers back to палату.

So:

• в палату, где уже спала...
• into a ward, where ... was already sleeping

It introduces a clause giving more information about the ward.

Because the grammatical subject is маленькая девочка, which is:

• singular
• feminine

So the past tense verb must agree with it:

• спал = masculine singular
• спала = feminine singular
• спали = plural

Since девочка is feminine singular, спала is the correct form.

Yes, с мамой means with (her) mother.

The preposition с in the meaning with takes the instrumental case:

• мама → мамой

So:

• с мамой = with mother / with her mother

Russian often does not use a possessive like её if the relationship is obvious from context. In English we usually say with her mother, but in Russian с мамой is completely natural.

Grammatically, the verb спала agrees only with маленькая девочка.

So the strict grammatical meaning is:

• the little girl was sleeping
• with her mother = the mother was there with her

If Russian wanted to say that both were sleeping, it would more naturally use a plural verb, for example:

• где уже спали маленькая девочка с мамой
  = where the little girl and her mother were already sleeping

So in your sentence, the girl is definitely the one marked as sleeping. The mother is present, but the sentence does not explicitly state that she was asleep too.

Уже means already, and in Russian it is often placed before the word or phrase it modifies most directly.

Here:

• где уже спала маленькая девочка...
• where a little girl was already sleeping...

This word order is very natural. It emphasizes that when the speaker was placed in the ward, the girl was already asleep there.

Russian word order is flexible, but this placement sounds normal and smooth.

Положить literally often means to put / to lay, but in medical or everyday contexts it can naturally mean:

• to place
• to put someone somewhere
• in hospital contexts, sometimes almost to admit / put in a room

So меня положили в палату is idiomatic and natural.

A verb like поместили would also be possible in some contexts, but it sounds more formal or bookish:

• Меня поместили в палату = I was placed in a ward

Положили sounds more everyday and conversational.

Because the sentence describes a completed action: after the examination, they put the speaker into the ward.

• положили = perfective, completed action
• клали = imperfective, ongoing/repeated process

Here the point is the result: the speaker ended up in the ward.

So perfective is the natural choice:

• После осмотра меня положили в палату
  = After the examination, they put me in a ward.

If you used клали, it would sound unusual here unless you were focusing on the process itself or repeated action.

It breaks down like this:

• После осмотра = After the examination
• меня ненадолго положили в палату = they put me in a ward for a short while
• где уже спала маленькая девочка с мамой = where a little girl with her mother was already sleeping

So the sentence has:

1. a time expression
2. the main clause
3. a subordinate clause describing the ward

That is why it may feel long, but each part is doing a clear job.