bleeding after sex

Whenever me and my boyfriend have sex, sometimes I’ll notice when I go to the bathroom the day after I notice a little bit of blood on the toilet paper, since we have rough sex and not a ton of foreplay my vagina is usually sore after too so I looked at my vagina after and noticed small tears on my vaginal opening and wondered if it’s because of the friction, it’s very light blood and it’s barely noticeable but it still worries me. I’ve been checked for stds and didn’t have any and he also hadn’t done anything where he could’ve gotten an std before me. Is this something I should be worried about or is this pretty normal ? I’m gonna try lube next time to see if it helps.