Bloody Condom freaked me Out

So me(19M) and my gf(17F) of a few months now have been having sex pretty consistently and damn good sex if I do say so myself. I was having some trouble finishing at first but it was solve with some better communication. But something happened recently that has me genuinely freaked out. She was on her period and it didn’t bother me(as I’ve had sex with other people before who were on their period), and she even warned me that she had a heavy flow. But I persisted onward and went through with it… Little to say, I think I’m traumatized and I may never view sex the same way. First off, it was messy, blood was oozing out constantly and the sound it made when I was pounding in and out, genuinely was bothering me. I finished strangely quick and when I pulled out the condom was covered in blood, absolutely drenched in it. I looked at my hands too were which were also covered in blood. I started to panic for some reason, my hand started shaking as I got this terrible feeling wash over me that I had done something terribly wrong, I felt violated and damaged. I started shaking more and crying, when my girlfriend noticed she asked what was happening and if I was okay. I left the room and walked into my bathroom to get a shower and I still saw the blood on my hands, I got this overwhelming feeling of being judged horribly. I felt like I had murdered someone almost. I’m not the most religious person ever but I am Catholic, and I have to say this was like nothing I’d ever felt before, and it’s the closest thing I’ve ever felt to being judged by like a higher power and it’s been looming over me for days now. I’ve been scared to have sex again, and my girlfriend has been asking me if I’m okay and if period sex bothered me that much but I don’t know how to explain myself without hurting her feelings or making her feel like im blaming her for what happened when its all me and my internal dread. I told a friend about what happened and he said I just have “a bad case of post-nut clarity” but Idk, it feels like I’ve been judged or genuinely condemned or something. I’m worried this will affect my relationship with my girlfriend who I genuinely love and want to marry one day and our sex life as a whole. I’m curious if anyone has any thoughts or ideas. And before anyone asks, I do plan on talking with my partner eventually about what happened when I feel emotionally ready.