Learn Hardcore Spanish (Latin America): Después de comer demasiado, me duele el estómago.

In Spanish, when you use después de and the subject of the second action is the same as the subject of the main verb, you normally use an infinitive:

Después de comer demasiado, me duele el estómago.
After eating too much, my stomach hurts.

Here, the implied subject of comer is yo (the same as me duele).

If you want to use a conjugated verb, you normally add que:

Después de que comí demasiado, me dolió el estómago.
After I ate too much, my stomach hurt.

So:

después de + infinitive = after doing something (same subject)
después de que + conjugated verb = after (someone) did something

Why do you say me duele el estómago instead of mi estómago duele?

Spanish usually expresses pain with the structure:

(Indirect object pronoun) + duele / duelen + body part

So:

Me duele el estómago. = My stomach hurts (to me).
Le duelen los pies. = His/Her feet hurt.

The literal idea is “The stomach hurts to me,” not “I hurt my stomach.”

Mi estómago duele is grammatically possible but sounds unusual and less natural. Native speakers almost always use me duele el estómago or tengo dolor de estómago.

What is the function of me in me duele el estómago? Is it reflexive?

Me here is not reflexive; it’s an indirect object pronoun.

doler works like gustar:
- Me duele el estómago. = The stomach hurts me.
- Me gusta el café. = I like coffee (literally: Coffee pleases me.)

So:

me = to me
te = to you
le = to him/her/you (formal)
nos = to us
les = to them / you all

They show who experiences the pain, not who performs an action.

Why is it el estómago and not mi estómago?

With body parts and clothing, Spanish typically uses:

Definite article (el, la, los, las)
- body part
Plus an indirect object or reflexive pronoun to show whose body part it is.

Examples:

Me duele la cabeza. = My head hurts.
Me lavé las manos. = I washed my hands.
Le cortaron el pelo. = They cut his/her hair.

Because me already indicates “to me,” you don’t need mi.
Mi estómago is not wrong, but me duele el estómago is what people naturally say.

Can I change the word order and say Me duele el estómago después de comer demasiado?

Yes. Both are correct:

Después de comer demasiado, me duele el estómago.
Me duele el estómago después de comer demasiado.

The difference is just emphasis:

Starting with Después de comer demasiado highlights the cause first (eating too much).
Starting with Me duele el estómago highlights the symptom (the pain) first.

Grammatically, both are fine and natural.

What exactly does demasiado mean here? Is it “too much” or “too many”?

In this sentence, demasiado is an adverb modifying the verb comer:

comer demasiado = to eat too much

As an adverb, demasiado does not change for gender or number.

But demasiado can also be an adjective, and then it does change:

demasiada comida = too much food
demasiados tacos = too many tacos
demasiadas bebidas = too many drinks

Here, because it modifies comer (a verb), it stays in the neutral form demasiado.

Could I say Después de que como demasiado, me duele el estómago instead?

You can, but it sounds less natural in this specific, general-habit sentence.

Después de comer demasiado, me duele el estómago.
Sounds like a general pattern/habit: whenever I eat too much, my stomach hurts.
Después de que como demasiado, me duele el estómago.
Grammatically correct, but a bit heavier; it can sound more like you’re talking about specific occasions, depending on context.

More typical with a specific time frame is:

Después de que comí demasiado, me dolió el estómago.
After I ate too much, my stomach hurt.

So for general statements, después de + infinitive is very natural.

Why is duele in the present tense? Shouldn’t it be past if it happens after eating?

Spanish is mirroring the English structure:

Después de comer demasiado, me duele el estómago.
After eating too much, my stomach hurts.

Both describe a general or current situation: whenever / when I eat too much, my stomach hurts.

If you want to talk about a past event, you change both verbs:

Después de comer demasiado, me dolió el estómago.
After eating too much, my stomach hurt. (on one specific occasion)
Después de que comí demasiado, me dolió el estómago.

So present tense is correct if you mean this is something that happens now or usually happens.

Is después de always followed by de, or can I say después comer demasiado?

You must keep de before the infinitive:

✅ Después de comer demasiado, me duele el estómago.
❌ Después comer demasiado, me duele el estómago.

Rules:

después de + infinitive → After doing something
después de + noun → After something
- Después de la cena, me duele el estómago.
después de que + conjugated verb → After (someone) did something
- Después de que comí demasiado, me dolió el estómago.

Are there other natural ways to say this in Latin American Spanish?

Yes, some common alternatives:

Tengo dolor de estómago después de comer demasiado.
I have a stomachache after eating too much.
Después de comer demasiado, se me revuelve el estómago.
(More colloquial: “My stomach gets upset after I eat too much.”)
Cuando como demasiado, me duele el estómago.
When I eat too much, my stomach hurts. (general habit)

In everyday Latin American speech, me duele el estómago and tengo dolor de estómago are especially common.