help :(

k • chill vibes
okay, so i was supposed to start my period like 3 days ago and i kept feeling like i was about to and haven't yet then i thought i started but when i went to change my tampon it was a brown discharge looking. and when i wipe it's like a light brown color.. i have no idea if that's normal or not?? 
also i'm freaking out because me and my boyfriend did have sex tuesday 😭