I have been on birth control but last month I wasn't so good about takin it. I had my period about 1-2 weeks early  last month and at the end of the pack I stopped taking the medication for a few days. My boyfriend and I have sex just about every other day and he came inside me. Come to find I was ovulating, at least I'm pretty sure I was. Now it been about three weeks since we had sex after i ovulated. I took a pregnancy test about a week ago and it said it was negative. However, I have been very tired, fatigued, and my appetite had been through the rough. But I have lost about 5 pounds and I don't know why.  Is there a possibility that I am actually pregnant? Has anyone else had something similar happen to them?