I Have Recently Had Unprotected Sex With My Boyfriend. I

I have recently had unprotected sex with my boyfriend. I have been getting all the symptoms of being pregnant. My lower stomach has been getting cramps, neck and back pains, really really tired during the day (sleeping through the day), food cravings and I just have the feeling that I am. I took two pregnancy tests, both came up negative. I'm about 5 days away from my period. Is there anyway I could be pregnant?