Why does my eye hurt when I blink?

Everytime I blink(right eye), The bottom right side of my eye hurts a lot. It feels similar to someone is poking the bottom right side really hard everytime I blink. Does anyone know why this is happening?
Answers:    I take that and it is most probably dirt or grit or possibly an eyelash that is stuck in within. Get some saline eye solution and wash out your eye and be careful around dust and so on. :)
Most expected an eyelash fell off, into your eye and is causing the irritation. This happen to me a lot. Just hold your right eyelid closed, and roll around your left eye, by looking around terribly quickly without turning your pave the way. This should cause right eyeball to shift around, and the eyelash should be out enough so that you can give somebody a lift it out. It might be a sty (sp?) on your eyelid that is moving every time you blink to cause the discomfort. I would make a contribution it another day or so.