wtf is this

I know we see these all the time but this has never happened to me and my circumstances are a little different.. I got on birth control at the end of may. I haven’t gotten my period since then. so of course i’m freaking out that i might be pregnant. but the other day i began to feel a little crampy and even noticed some blood so i assumes i started my period and the birth control just made my periods extremely irregular and very light. I also noticed the past two days my “period” blood was slightly brown which i’ve learned meant that it was old blood. I found that a bit weird since I just started my period. but then i just went to the bathroom and noticed it was fresh blood after i wiped. AND THIS CAME OUT OF ME

I understand it could very well be a part of my uterine wall but the circumstances don’t add up. please help :((