So I had unprotected sex & thought I was pregnant , I had my period but it wasn't a normal period I had it for only 3 days and it wasn't like a big flow it was a lil one but I was getting the symptoms as if I was pregnant ? I haven't tested myself because I got the light period but now I'm starting to gain weight , grave so much sweets and get tired easily , could I be pregnant and not know it ? HELP!