Help!!! Am I Pregnant???

I just ended my period on the 28th, stopped ovulating on the 7th and I’m not supposed to start my period until the 20th. I went to the bathroom and I guess I bled it’s like dark blood, what does this mean? Help. Also I am not on birth control. My boobs feel extra plump and idk I just feel kinda weird! Also I had sex on some of the ovulation days. Thanks!!