Woke up this morning and my left eye hurts and my eyelid is swollen. What can cause this?

Infection or injury. Infection or injury is the most likely cause. See an ophthalmologist if this does not clear up in a few days.
Possible infection. The first thing we need to know is if the pain in the eyelid in the area that is swollen or if it is actually the eyeball that is painful. If the eyelid is painful, most likely there is an infection in the lid which need to be treated with topicla and possibly oral antibiotics. If the eyeball is painful, then the swelling in the eyelid is a reaction to whatever is causing the pain.

Related Questions

This morning my left eye hurts and my eyelid is swollen. What caused this?

Multiple causes. Sudden soreness and swelling of the eye or eyelids can have multiple causes. Most common would be a chalazion or a hordeolum (stye). Other infectious and inflammatory causes are possible, including conjunctivitis, iritis, sinusitis, etc. You can try a warm compress (clean washcloth rinsed with very warm tap water) for a day or two, but see an eye md promptly if the symptoms are not resolved soon. Read more...