Tengo sueño, así que voy a acostarme temprano.

In Spanish, some physical states are expressed with tener rather than ser or estar.

So:

• tengo sueño = I’m sleepy
• tengo hambre = I’m hungry
• tengo sed = I’m thirsty

A literal word-for-word translation into English does not work here. Spanish treats sleepiness as something you have, not something you are.

They are related, but not identical.

• Tengo sueño = I feel sleepy; I want to sleep.
• Estoy cansado/a = I’m tired; I lack energy.

You can be:

• cansado/a without being sleepy
• con sueño or tener sueño specifically when you feel like sleeping

So in this sentence, tengo sueño fits well because it naturally leads to going to bed.

Así que means so, therefore, or so then.

It connects a cause and a result:

• Tengo sueño, así que voy a acostarme temprano.
• I’m sleepy, so I’m going to go to bed early.

It is very common in everyday Spanish.

A few similar connectors are:

• por eso = for that reason / that’s why
• entonces = then / so

But así que is especially natural for linking one idea directly to the consequence.

Ir a + infinitive is a very common way to talk about the near future in Spanish, just like going to in English.

• voy a acostarme = I’m going to go to bed
• me acostaré = I will go to bed

Both are correct, but voy a acostarme sounds more conversational and immediate. In everyday speech, Spanish often prefers this structure over the simple future.

Because Spanish uses the pattern:

ir + a + infinitive

Examples:

• voy a dormir
• vamos a salir
• van a comer

So:

• voy = I go
• a = to
• acostarme = lie down / go to bed

Together, it forms the future idea I’m going to go to bed.

Because acostarse is a reflexive verb.

Its infinitive form is:

• acostar = to lay something down
• acostarse = to lie down / go to bed

When a reflexive verb follows another conjugated verb, the reflexive pronoun can usually go in two places:

• voy a acostarme
• me voy a acostar

Both are correct and mean the same thing.

In this sentence, acostarme has the pronoun attached to the infinitive, which is completely natural.

Here, acostarse means to go to bed or to lie down to sleep.

It does not necessarily mean that the person is already asleep. It focuses on the action of getting into bed.

Compare:

• acostarse = to go to bed / lie down
• dormirse = to fall asleep
• dormir = to sleep

So:

• voy a acostarme temprano = I’m going to bed early
• voy a dormirme temprano would sound less natural in most contexts, because it focuses on actually falling asleep

Yes. That is equally correct.

You have two standard options with reflexive verbs after another conjugated verb:

1. Put the pronoun before the first verb:

   • me voy a acostar

2. Attach it to the infinitive:

   • voy a acostarme

Both are natural. The meaning is the same.

Learners often find the second version easier to recognize because it keeps the infinitive together:

• acostar + me = acostarme

Because temprano is commonly used as an adverb meaning early.

So:

• acostarme temprano = go to bed early

Spanish often uses words like temprano, tarde, and rápido as adverbs without needing the -mente form.

Although tempranamente exists, it sounds much less natural in everyday speech here. Temprano is the normal choice.

The written accent shows the correct stress: a-SÍ.

In así que, the word así keeps its accent mark. Accent marks in Spanish are an important part of spelling and sometimes help distinguish pronunciation or different words.

So you should always write:

• así que

not:

• asi que

Yes, it is completely natural in Spain.

A speaker from Spain might also say:

• Tengo sueño, así que me voy a acostar temprano.
• Tengo sueño, así que me voy a la cama temprano.
• Estoy cansado/a, así que me acuesto temprano hoy.

But your original sentence sounds very normal and idiomatic in Spain:

• Tengo sueño, así que voy a acostarme temprano.