help please !?

so i had sex with my boyfriend for the first time a week ago and i was supposed to start my period on tuesday but i'm late today we didn't have sex but he was fingering me and i started bleeding. we stopped and he got me a tampon and i took a nap i changed my tampon after that it wasn't full like it normally would be because i had a regular tampon in but later when i changed my tampon again there was blood but again not as much as normal. i usually have a heavy flow but it's really light right now. my blood is still the same color but i'm scared i might be pregnant.