What Causes Grayish Discharge From The Vagina With Irregular Periods?

Hi, I was having a number of problems with my cycle, like irregularities and more pain than normal. Last week I had an abnormal period that was suddenly interrupted and I discharged a grey tissue-like matter. Then, at the end of my period, I discharged even more of this matter and this time it was grey and pink. I went to the gynecologist and got a transvaginal ultrasound. After that, the doctor informed me I have polycystic ovaries and sent me a beta Hgc quantitative test. The test came out very low, 2mUI/mL, but I am still very worried about all this. Could I have had a miscarriage or what might that grey thing have been?