Okay I gotten my cycle 2-9-11 and it was supposed to come on the 2-10-11 and when it came it was very light and not heavy at all and it went away 2-12-11 now I'm feeling a little weak and stomach hurts could I be pregnant?

Did you have sex?

To be sure, get a home pregnancy test. A period generally means you are not pregnant and this one came around the time you'd expect it. If it was very light, just a few drops of blood, it's still possible to be pregnant.