Could The Pink-grey Clot During My Period Be A Sign Of Miscarriage Or Related To My Birth Control And Endometriosis?

I just got my period last night and this morning I noticed a pink/grey clot that I ve never seen before. It s about the size of a knuckle and doesn t look like the normal period blood clots that I m used to seeing. I don t know if this is a miscarriage. My partner and I use condoms and I am on the pill but I stopped taking it for a couple of days to get my period because I ve been feeling cramps so just wanted to get it over with. I have a history of endometriosis and I had a laproscopy 2 years ago to get it removed and they told me it will probably affect my fertility because it was severe and all over my ovaries. I have had some pain and bleeding during sex lately so maybe that s relevant? From what I could find googling this, it could either be because of birth control or a miscarriage. Can anyone help? I have photos if needed but didn t want to post here. Thanks in advance.