אחרי כל השאלות האלה הגעתי למסקנה שאני צריכה עוד זמן.

Yes. אחרי means after, so אחרי כל השאלות האלה is literally after all these questions.

A natural English translation might sound a little freer, like:

• After all these questions...
• After all those questions...
• Following all these questions...

In Hebrew, this opening phrase sets the context for what follows.

Hebrew has a fixed word order here:

• כל = all
• השאלות = the questions
• האלה = these

So the pattern is:

כל + noun + demonstrative

That gives: כל השאלות האלה = all these questions

Unlike English, where these comes before the noun, in Hebrew האלה usually comes after the noun:

• השאלות האלה = these questions

Yes, but Hebrew marks this differently from English.

In Hebrew, when you say this / these / that / those after a noun, the noun is usually also made definite with ה־.

So:

• שאלות = questions
• השאלות האלה = these questions

This is normal Hebrew structure. Literally it looks like:

• the questions האלה but in natural English it is just:
• these questions

The singular would be:

• השאלה הזאת = this question or
• השאלה הזו = this question

Your sentence uses the plural:

• השאלות האלה = these questions

Useful comparison:

• שאלה = question
• שאלות = questions

הגעתי למסקנה is a very common Hebrew expression meaning:

• I came to the conclusion
• I reached the conclusion

Breakdown:

• הגעתי = I arrived / I reached
• למסקנה = to the conclusion

So literally it is something like:

• I arrived at a conclusion

But in English, the natural phrase is:

• I came to the conclusion

למסקנה is made from:

• ל־ = to
• מסקנה = conclusion

Since מסקנה here is definite in the expression to the conclusion, the ל־ combines with ה־:

• ל + ה + מסקנה → למסקנה

This kind of combination is very common in Hebrew:

• ל + ה becomes לַ / לָ / לֶ in pronunciation, and in writing you often just see ל attached to the word.

So למסקנה means to the conclusion.

The ש־ here means that.

So:

• שאני צריכה עוד זמן = that I need more time

This is a very common way to introduce a subordinate clause in Hebrew.

Full structure:

• הגעתי למסקנה = I came to the conclusion
• שאני צריכה עוד זמן = that I need more time

Together:

• I came to the conclusion that I need more time

Because in the present tense, Hebrew usually needs the pronoun more than English learners might expect.

צריכה tells you:

• feminine
• singular

But it does not clearly tell you the person the way a past-tense verb does. So אני is usually included to show I.

Compare:

• אני צריכה = I need / I am needing
• היא צריכה = she needs

Since צריכה could match more than one subject, אני helps make it clear.

Because the speaker is female.

In Hebrew, the present-tense form agrees with gender and number.

• אני צריך = I need (said by a male speaker)
• אני צריכה = I need (said by a female speaker)

So this sentence is spoken by a woman or girl.

It would be:

אחרי כל השאלות האלה הגעתי למסקנה שאני צריך עוד זמן.

The only change is:

• צריכה → צריך

Everything else stays the same.

Because עוד often means more / additional / another.

So:

• עוד זמן = more time
• literally: additional time

This is very natural Hebrew.

You can also hear:

• אני צריך עוד זמן = I need more time
• תן לי עוד דקה = give me another minute

In many cases, עוד is the normal word for more when talking about an additional amount.

Yes, but the nuance is a little different.

• עוד זמן = more time / some additional time
• יותר זמן = more time in a more comparative sense

In your sentence, עוד זמן sounds very natural because the idea is:

• I need some additional time

If you said יותר זמן, it might sound a bit more like:

• I need more time than this
• I need a greater amount of time

Both can work, but עוד זמן is especially common in this kind of sentence.

Because the sentence describes two different time relationships:

• הגעתי למסקנה = a completed event in the past
  (I came to the conclusion)
• שאני צריכה עוד זמן = the content of that conclusion, which is true now
  (that I need more time)

So the sentence means:

• At some point, I reached a conclusion.
• That conclusion is: I currently need more time.

This mix of past + present is very normal.

Yes, the given word order is natural, and so is the version starting with הגעתי למסקנה.

Your sentence:

• אחרי כל השאלות האלה הגעתי למסקנה שאני צריכה עוד זמן.
• After all these questions, I came to the conclusion that I need more time.

Possible alternative:

• הגעתי למסקנה שאני צריכה עוד זמן אחרי כל השאלות האלה.

But that version sounds a little different in emphasis. The original puts the focus first on the circumstances:

• After all these questions...

So the original is very natural if you want to foreground that idea.

A simple pronunciation guide is:

Akharei kol ha-she'elot ha-eleh higáti le-maskaná she-aní tsrikhá od zman.

Approximate stress:

• akharei
• ha-she'eLOT
• ha-ELeh
• higA'ti
• le-maskaNA
• she-aNI
• tsriKHA
• od
• zman

A few pronunciation notes:

• ח in אחרי is a throaty sound, not like English h
• שאלות has a slight break because of the א: she-e-lot
• צריכה is often pronounced roughly tsri-kha

It is mostly neutral standard Hebrew.

Nothing in it is unusually formal or slangy. It would sound natural in:

• conversation
• writing
• emails
• everyday speech

The expression הגעתי למסקנה is a little more thoughtful or reflective than just saying:

• אני חושבת שאני צריכה עוד זמן = I think I need more time

So it sounds a bit more deliberate, but still completely normal.