Sorry for the TMI but What is this?

Back Story....Me & my husband had sex unprotected the week I was fertile following the week after but her pulled out every time, Until 8 days before my period was suppose come he accidentally went in inside me!

Well my whole life I have been super regular with my periods. Never been on birth control, Every month when glow predicts I’m gunna start my period, is the exact day I do....that regular!

Well this month.....I was at work 3 days before my expected period and got a REALLY sharp pain in my stomach & it felt like I had started my period, so I go to the bathroom & it is this small amount of brown discharge. Did think munch of it, ask my co-workers they said it could be spotting, that I could possibly be pregnant...I put a tampon in incase it continued....The rest of the day the sharp pain continued & I felt sick. Next Day I figured out it was my period because the substance turned really read and it was super heavy, Same thing, Sharp pain all day though! ( Side Not, My periods are normally super light & I never have cramps except the first day when I start. I mainly just have mood swings)

Well this morning when I got up, I went to bathroom Bc last night I woke up with a sharp pain and like I was gunna get sick. I take my tampon out & I wipe & I get this....My period had never looked like this before. Can you guys tell me what this is???