What is it???

So I’ve been lightly bleeding for about a week and a half now. At first it was brown discharge but then turned to blood. I thought I had just started my period but it was so extremely light. I didn’t couldn’t even cover a panty liner. Well I woke up this morning with terrible cramps. Almost unbearable. I didn’t think anything about it. Well I was wearing a pad today and when I want to check is there was a HUGE light brown glob with a little blood around it. It was kinda in a circle and was really thick. What is it and should I be worried??? Is there anyway it was a miscarriage and I just didnt know I was pregnant??