OK so about two weeks ago I had my period and just today I started bleeding again. What does this mean?

I'm guessing from where you've posted this that you're very young, probably just starting to have your period? Yes? If that's the case, I wouldn't worry about it. It takes a while for your periods to become regular. When I first got mine I would go two months without one, then just 3 weeks. It was totally unpredictable.

justcurious55 is absolutely right. If you are very young (which you seem to be) having your period at odd times for a few years before it will regulate.

I'm seventeen

It's probably still nothing to worry about. Sometimes you can have breakthrough bleeding or spotting between periods. Unless this keeps happening or you begin bleeding unusually heavy or something like that, I wouldn't worry. A one time funky cycle usually isn't anything to stress over.