Not sure

So me and my boyfriend had sex about a month ago and like a week later my period was a week early but it was super light which is not normal all the females in my family including me have heavy periods so it didn't seem right to me. And the last two weeks I've been feeling like crap. I've been throwing up and my stomach feels funny and my boobs feel weird...my boyfriend thinks I might be pregnant but I don't think I could be since I had my period