Learn Spanish (Spain): Hoy me duele la espalda.

In Spanish, when you talk about body parts, you usually use definite articles like el or la (the) instead of possessive words like mi (my). Because you already said me (to me) earlier in the sentence, it is completely clear whose back is hurting!

Why is it me duele instead of "yo duele"?

The verb doler (to hurt) works a lot like the verb gustar (to like). Instead of saying "I have a hurting back," the Spanish phrasing translates closer to "The back brings pain to me." Here, me means "to me," and duele means "it hurts."

If I wanted to say "my legs hurt today," would I still use duele?

No, you would use duelen. Because the sentence literally means "the back hurts me," the verb must match the thing that is hurting (the subject). Since la espalda is singular, you use the singular duele. If it were a plural body part like las piernas (the legs), you would use the plural duelen: Hoy me duelen las piernas.

If the dictionary infinitive is doler, why is it spelled duele here?