I started my depo shot on June 11th and waited two weeks after to have sex . After the sex like a week later I got this brown/black discharge for 4 days then it stopped and I got my period it started off light then got really heavy yesterday ? I was experiencing very bad cramps/back pains the day before I felt naseous.. While at work I went to the bathroom and saw this pink thick tissue the size of my thumb .... Idk what's going on can anyone give me some insight .