Después de la caída, me duele la muñeca.

Because después usually needs de before a noun or pronoun.

• después de la caída = after the fall
• después de comer = after eating
• después de eso = after that

You can use después by itself only when the rest is understood:

• Primero comemos y después salimos. = First we eat and then we go out.

So in this sentence, de is required because it is followed by la caída.

Caída is a noun meaning fall.

It comes from the verb caer = to fall.

• caer → caída
• la caída = the fall

So:

• Después de la caída = After the fall

It is a very common way to talk about an accident, stumble, or physical fall.

Spanish uses doler differently from English.

In English, we often say:

• My wrist hurts

But in Spanish, the structure is more like:

• The wrist hurts me

So:

• me = to me
• duele = hurts
• la muñeca = the wrist

That is why me duele la muñeca is the normal Spanish pattern.

You may hear English speakers try to translate word-for-word and say something unnatural. The natural Spanish structure with doler is:

• me duele la cabeza = my head hurts
• te duelen los pies = your feet hurt
• le duele el brazo = his/her arm hurts

With body parts, Spanish usually prefers:

• an indirect object pronoun (me, te, le, nos, os, les)
• plus the definite article (el, la, los, las)

So instead of saying my wrist, Spanish often says the wrist, while the pronoun shows whose wrist it is.

• me duele la muñeca = my wrist hurts
• me duele la cabeza = my head hurts
• se lavó las manos = he/she washed his/her hands

Using mi muñeca is possible in some cases, but here la muñeca is the most natural choice.

Because the subject is singular: la muñeca.

With doler, the verb agrees with the thing that hurts, not with the person.

• me duele la muñeca → one wrist → singular → duele
• me duelen las muñecas → two wrists → plural → duelen

More examples:

• me duele el brazo = my arm hurts
• me duelen los brazos = my arms hurt

Yes, muñeca can mean both wrist and doll.

The meaning depends on context.

In this sentence:

• Después de la caída, me duele la muñeca.

the context of a fall and pain makes wrist the obvious meaning.

Examples:

• La niña tiene una muñeca nueva. = The girl has a new doll.
• Me torcí la muñeca. = I twisted my wrist.

So this is one of those Spanish words with two meanings.

No. The me here is not a reflexive pronoun; it is an indirect object pronoun.

It tells you who is affected:

• me = to me
• te = to you
• le = to him/her
• nos = to us

So:

• me duele la muñeca = the wrist hurts me
• te duele la espalda = your back hurts
• le duelen las piernas = his/her legs hurt

This is different from a reflexive verb like:

• me lavo = I wash myself

The comma separates the introductory phrase from the main clause.

• Después de la caída = introductory time phrase
• me duele la muñeca = main clause

So the comma helps readability:

• Después de la caída, me duele la muñeca.

In short sentences, Spanish punctuation can sometimes be flexible, but this comma is very natural and clear.

Yes, that is possible, but it means something slightly different in structure.

• Después de la caída = after the fall
  
  • uses a noun: la caída
• Después de caer = after falling
  
  • uses an infinitive verb: caer

Both are correct. The original sentence sounds very natural and focuses on the fall as an event.

Caída is pronounced roughly ka-EE-da.

The accent mark shows that the i is stressed and pronounced separately from the a. So it is not one smooth diphthong; it has a break:

• ca-í-da

Without the accent, Spanish spelling rules would suggest a different pronunciation.

This is a common pattern in words where a weak vowel like i or u is stressed next to another vowel:

• caída
• oído
• país

A rough English-style pronunciation is:

• moo-NYE-ka

Key points:

• ñ sounds like ny in canyon
• mu sounds like moo
• stress is on ñe: mu-ÑE-ca

So the whole word is approximately moo-NYE-ka.

It is standard Spanish and would be understood everywhere.

Nothing in Después de la caída, me duele la muñeca is uniquely Spain-only grammar. Speakers in Spain and Latin America would all understand it and would commonly say something very similar.

The main differences across regions would be pronunciation, not the basic grammar of this sentence.