Eye twitching is a normal phenomenon and come and go itself. Sometimes, it just last for several minutes. Sometimes, it last for several hours. In some serious cases. it can also last for several days. So, i can't give you an answer how long does your eye twitching last. And eye twitching can be caused by strained eyes, dry eyes and stress etc. If you have very several eye twitching, you'd better visit an eye doctor.
As we know that eye twitching is an involuntary eyelid muscle contraction which usually affects the lower eyelid. A twitch sometimes develops during times of increased stress. Eye twitching has also been associated with high caffeine intake, fatigue. It can also occur after reading or working on a computer for prolonged periods of time. So when your eyes are twitching, it's a sign to have a break. Sometimes a twitch will go away following a good night's sleep, but a stubborn twitch may last as long as three weeks. Anyway, it all depends on your situation. If your eyes are twitching for a long time, maybe you should go and see a doctor as soon as possible.