Hey, I had my period for a few days, seemed like normal with a little back pain as usual, then it went away for about 2-3 days, and I was sure it was completely gone. Just today though, it seems that it has come back, but I've been having huge stomach pains and it has been really heavy. I'm a smoker (trying to quit, using an e-cig when I remember to charge it), and I'm on the patch... any idea? Could I be pregnant, or dehydrated...? I need advice :(