Today when i woke up my left eye looks fine but started paining when i blink. the lower side of the eye on the lower eyelid hurts while blinking. maybe while sleeping got hit on my eye. should i wait for 2-3 days to heal on it's own?

There could be an eyelash or some foreign body impacted there or you have early symptom of a stye. You should splash water into the eye to flush the hair or that foreign body out. If you see the redness on the edge of the eyelid with a small bump then it is a stye or there is a bump on the inside of the eyelid, it is a chalazion. For these, you can apply warm compress three to four times a day.

Sounds like the beginning of a chalazion (stye). If the eyelid is sore to touch and is swollen try hot compresses several times a day. If the scratchy pain persists see an opthalmologist.

If the eye hurts when you blink and feels better when you keep your eyes closed, it's likely a corneal abrasion and will heal in a day or so. If the eyelid (especially at the margin) hurts or is focally red, it's probably a hordeolum (stye) and may respond to warm compresses. If is doesn't improve shortly or if it is accompanied by decreased vision, you should see an ophthalmologist.