Eye swelling with severe pain can happen because of infection, allergy, insect bite, blocked oil glands, eye strain, sinus infection, or inflammation around the eyelid. If the swelling appeared suddenly after waking up, it may also be related to rubbing the eye during sleep, irritation from dust, or an early eyelid infection such as a stye. Pain, along with swelling, should be observed carefully because some eye infections can worsen quickly if ignored. Avoid touching, rubbing, or pressing the swollen eye because this may increase irritation and spread infection. A clean warm compress over the closed eyelid for short periods may help reduce discomfort in some cases. Resting the eyes, avoiding screen strain, and maintaining proper hygiene may also support recovery. Do not use leftover eye drops, steroid creams, or random medicines without proper examination because the exact cause may differ. A medical evaluation is important if the swelling is increasing, vision becomes blurred, pus develops, or the pain becomes severe. Eye problems associated with fever, redness spreading around the eye, or difficulty opening the eye may need urgent attention.