Potvrdila sam termin kod doktorice za petak ujutro.

In Croatian past tense, the auxiliary sam is a clitic, and clitics usually go in the second position of the sentence or clause.

So in:

Potvrdila sam termin...

the first element is potvrdila, and sam comes right after it.

This is very normal Croatian word order. You can also hear other orders depending on emphasis, for example:

• Ja sam potvrdila termin. = I confirmed the appointment.
• Termin sam potvrdila jučer. = It was the appointment that I confirmed yesterday.

So potvrdila sam is not strange at all; it is a standard and common pattern.

Because the speaker is female.

In the Croatian past tense, the main verb is a past participle, and it agrees with the subject in gender and number.

So:

• potvrdila sam = I confirmed (speaker is female)
• potvrdio sam = I confirmed (speaker is male)

The auxiliary sam tells you it is first person singular (I), and potvrdila/potvrdio shows the speaker’s gender.

Croatian often leaves out subject pronouns when they are already clear from the verb form.

Here, sam already tells you I, and potvrdila tells you the speaker is female. So ja is unnecessary unless you want emphasis.

Compare:

• Potvrdila sam termin. = neutral, natural
• Ja sam potvrdila termin. = emphasizes I confirmed it

English usually needs the pronoun, but Croatian often does not.

Termin is in the accusative singular because it is the direct object of potvrdila sam.

The dictionary form is nominative singular:

• termin = appointment / slot / term

Since termin is a masculine inanimate noun, its accusative singular is the same as its nominative singular:

• nominative: termin
• accusative: termin

That is why you do not see a visible change here.

Kod means something like at, with, or by in this kind of context, and it takes the genitive case.

So:

• doktorica = female doctor
• kod doktorice = with / at the female doctor’s

This is a very common way to talk about appointments:

• imam termin kod zubara = I have an appointment with the dentist
• bila sam kod liječnika = I was at the doctor’s

Because kod requires genitive, doktorica changes to doktorice.

Because after kod, Croatian uses the genitive case.

The noun changes like this:

• nominative: doktorica
• genitive: doktorice

So:

• doktorica = a female doctor
• kod doktorice = with the female doctor / at the female doctor’s

If it were a male doctor, you would usually get:

• kod doktora

This is a very important distinction.

Here, za petak ujutro means the appointment is scheduled for Friday morning.

• termin za petak ujutro = an appointment for Friday morning

But u petak ujutro usually tells you when something happened:

• Potvrdila sam termin u petak ujutro. = I confirmed the appointment on Friday morning.

So:

• za petak ujutro = the time of the appointment
• u petak ujutro = the time when the confirming happened

That is why za is used here.

After za in this meaning, Croatian uses the accusative.

So petak here is accusative singular. But just like termin, petak is a masculine inanimate noun, so its accusative looks the same as its nominative:

• nominative: petak
• accusative: petak

So the form does not visibly change, even though the case has changed.

Because ujutro is a fixed adverb meaning in the morning.

So:

• ujutro = in the morning

It is very common in time expressions:

• vidimo se ujutro = see you in the morning
• radim ujutro = I work in the morning

In this sentence, petak ujutro means Friday morning, and za petak ujutro means for Friday morning.

Yes. Croatian word order is fairly flexible, and changing it usually changes emphasis, not the basic meaning.

For example:

• Potvrdila sam termin kod doktorice za petak ujutro. = neutral
• Termin sam potvrdila kod doktorice za petak ujutro. = emphasis on the appointment
• Kod doktorice sam potvrdila termin za petak ujutro. = emphasis on with the doctor
• Za petak ujutro sam potvrdila termin kod doktorice. = emphasis on Friday morning

Not every version sounds equally natural in every context, but Croatian allows a lot more movement than English.

Yes, often you can.

• doktorica = female doctor
• liječnica = female physician / doctor

In many everyday situations, both can work. So you could also say:

Potvrdila sam termin kod liječnice za petak ujutro.

That may sound a little more formal or standard to some speakers, while doktorica is very common in everyday speech.

Yes. Potvrditi is a perfective verb, and it fits well here because confirming an appointment is seen as a completed action.

So:

• potvrditi = to confirm, to complete the act of confirming
• potvrdila sam = I confirmed

A learner might compare it with an imperfective partner such as potvrđivati, which would suggest repeated, ongoing, or habitual confirming, not one completed confirmation.

In this sentence, the idea is clearly one finished action, so the perfective verb is the natural choice.