Bleeding after orgasm

I have very irregular periods and I'm on the 13th day of my current one. It appeared to be finished earlier on today so I masterbated then had a nap, but when I woke up 30 min later I was having heavy bleeding. I'm almost wondering if the orgasm caused me to shed more uterine lining. Has anyone else experienced this or something similar and do y'all the orgasm is the cause for the bleeding?