Bleeding the day after sex

So, I should probably be calling my gyno or PCP right now instead of posting this (I'm going to after, promise), but I keep bleeding after I have sex with my boyfriend. It lasts for like 3 days and it's not heavy like a period, but it's definitely more than just spotting. It's happened many times now, and it's weird because it's never happened with anyone else I've had sex with (and I've been with guys who were bigger than he is if you know what I mean). It's definitely starting to scare me a bit.. and man, if I lose one more pair of Victoria's Secret panties to this imma freak out. 😤😣

Has anyone ever had this issue?