I had unprotected sex with my boyfriend on Jun the 30 now I'm having cramps and lower stomach pain also a little back pain.I started feeling like I had to throw up the first week after we had sex and I have no appetite. Yesterday we had sex again after I went home I noticed a spot of light red blood. I'm on birth control but many people said that they have gotten pregnant while on the shot so I'm wondering if these symptoms could be pregnancy symptoms