I need answers

Girls can anybody help me plz. Okay so I think I am pregnant. My symptoms are; bloated stomach, nausea, headache, mood swings, hungry almost all the time, weight gain, food cravings, and I'm sensitive to some smells. Anyways, my period is over a week late so I took a pregnancy test and it said negative. I was hoping maybe somebody knew what was going on. Thanks:)
Ps 
Me and my bf have been having unprotected sex.