Sen hemen sinirlenme; önce ne olduğunu sakince anlamaya çalış.

That is true: Turkish usually does not need subject pronouns, because the verb form already shows the person.

So this could also be:

Hemen sinirlenme; önce ne olduğunu sakince anlamaya çalış.

Adding sen gives extra emphasis or makes the command feel more directly aimed at the person:

• Sen hemen sinirlenme = You don’t get angry right away

It can sound a little more personal, contrastive, or firm.

Hemen means immediately, right away, or at once.

In this sentence, it tells you when not to get angry:

• hemen sinirlenme = don’t get angry immediately / right away

It is placed before the verb for a very natural Turkish word order.

Sinirlenme is the negative imperative for sen from the verb sinirlenmek, which means to get angry or to become irritated.

Breakdown:

• sinirlen- = verb stem
• -me = negative imperative marker for you singular

So:

• sinirlen = get angry
• sinirlenme = don’t get angry

Here it is a command or instruction, not a noun.

Because this sentence is giving a command/advice, not stating a fact.

Compare:

• Sinirlenme. = Don’t get angry.
• Sinirlenmezsin. = You do not get angry / you won’t get angry.

The first is imperative.
The second is indicative.

So in this sentence, sinirlenme is the correct form because the speaker is telling someone what to do.

Önce means first or before that.

It introduces the second instruction as something that should happen before reacting emotionally:

• önce ... anlamaya çalış = first, try to understand ...

So the whole sentence has this logic:

1. Don’t get angry immediately.
2. First, try to understand what happened.

Yes, this is one of the most common Turkish structures learners ask about.

Ne olduğunu means something like:

• what it is
• what happened
• what is going on

depending on context.

It comes from ne olmak in a subordinate clause, but Turkish turns that clause into a kind of noun phrase.

A helpful breakdown is:

• ne = what
• ol-duğ-u-nu

That last part contains several pieces:

• ol- = be / become / happen
• -duk / -dık / -dik / -duk type nominalizing suffix
• -u = 3rd person possessive
• -nu = accusative case

So ne olduğunu anlamak literally means something like to understand what it is / what happened.

The final -nu is the accusative case ending.

Why is it there? Because the whole phrase ne olduğunu is the object of anlamaya çalış:

• ne olduğunu = what happened / what it is
• anlamaya çalış = try to understand

So you are trying to understand that specific thing. In Turkish, these subordinate clauses often take case endings just like nouns do.

This is a very common pattern:

• Bunu biliyorum. = I know this.
• Ne olduğunu biliyorum. = I know what it is / what happened.

It can mean either, depending on context.

In this sentence, the most natural English idea is often:

• try to calmly understand what happened
• or try to calmly understand what’s going on

That is because ne olduğunu anlamak is a very common Turkish expression used when someone should first figure out the situation.

So the literal grammar may look like what it is, but the natural meaning is often broader.

Sakince means calmly.

It comes from:

• sakin = calm
• -ce / -ca = a suffix that often makes an adverb-like form

So:

• sakin = calm
• sakince = calmly / in a calm way

In this sentence, it modifies anlamaya çalış:

• sakince anlamaya çalış = try to understand calmly

Because anlamaya çalış means try to understand, which is softer and more realistic than simply saying understand.

Compare:

• Anla. = Understand.
• Anlamaya çalış. = Try to understand.

The second sounds more natural in advice like this. It suggests effort, patience, and process.

It comes from the common Turkish pattern:

verb + -(y)A + çalışmak = to try to do something

Here:

• anla- = understand
• -ma = verbal noun / infinitive-like form
• -ya = dative
• çalış = imperative of çalışmak

So:

• anlamaya çalış = try to understand

This is a very useful pattern:

• yapmaya çalış = try to do
• öğrenmeye çalış = try to learn
• dinlemeye çalış = try to listen

It is informal singular, because the commands are directed at sen.

The verb forms show that:

• sinirlenme
• anlamaya çalış

If you wanted to say the same thing politely or to more than one person, you would use siz forms:

• Hemen sinirlenmeyin; önce ne olduğunu sakince anlamaya çalışın.

So the original sentence is natural for speaking to one person in a direct but not necessarily rude way.

Turkish word order is somewhat flexible, but this version is very natural.

Current order:

Sen hemen sinirlenme; önce ne olduğunu sakince anlamaya çalış.

This emphasizes:

• hemen = right away
• önce = first
• sakince = calmly

Some rearrangements are possible, but they may shift emphasis. For example:

• Sen sinirlenme hemen sounds less natural here.
• Önce sakince ne olduğunu anlamaya çalış is also possible.

So the sentence is not completely fixed, but the original word order is smooth and idiomatic.