Light brown discharge before period

Hey ladies, i get my period in 3 days ( Thursday ) it’s Monday night! I’m currently on spring break, and I’m getting like kinda light brown discharge in my bathing suits. I sometimes will get different colored discharge before period but the internet is freaking me out, i had like a lil romantic moment with my boyfriend a few weeks ago and he slipped it in me twice but did not cum and wiped his dick for any precum the two times he did it. We are always safe and use protection but that was the only time in the heat of the moment that we ever haven’t, and again it was only twice and no cum. But now I’m panicking thinking It might be implantation bleeding, but i have anxiety and i overthink stuff.. please please let me know if this is normal to have kinda brownish discharge a few days before period!! I’m a senior and highschool and do not want to be pregnant, but I’m on spring break worrying and i don’t wanna be! Ease my mind!!