I agree with Joy, once the contractions become closer together and more painful, or if your water breaks then you need to call the hospital or your doc. Sometimes this can happen for days until the real deal starts. The hospital is there to help you through this time so if you are concerned or unsure just give them a call and they will be able to advise you of the best thing to do and be able to calm your nerves - good luck.
Amyy, it sounds like it could be early labor or false labor. Hang in there! When contractions become painful (can't walk or talk through them; you have to focus on your breathing to get through them) and are more consistent and closer together (about 4-5 minutes apart from the START of one to the START of the next) then call your doctor. Good luck!