My eyelid won't stop twitching.?

For the past three days,my eyelid has been twitching relentlessly. It's always twitched every now and again, of course, but it has never happened this consistently. It's not distracting me or anything. It's just really annoying, especially in school. People already think I'm crazy (and that I eat three dictionaries every morning for breakfast.), so a twitching eye probably won't help my case XD

Anyway, some help would be great. And a reason, too, since my grandparents have this idiotic habit of literally blaming all of my problems on the computer and I'd like a reasonable explanation to give them.