I had unprotected sex and took plan b 2 days later. I then got my period 4 days after I took plan b. The period I got was a month early. Im now a week late for my regular period and am experiencing pregnancy symptoms. I have cramps bloating and constipation. My nipples are tender as well. I took two pregnancy tests and they both were negative. Is there any chance I could be pregnant? And what are these symptoms from? I'm really scared. Please help