Possible miscarriage?

Reposting because I messed up the poll

Ive had two previous miscarriages at 7 weeks. Both times I began spotting at 6 weeks and fully miscarried at exactly 7 weeks. Both of these were also after I saw a heartbeat at 6+3 weeks.

Anyway, due to covid my doctor has not even seen me yet and my first appointment isn’t until 12 weeks, I’m 6 weeks today, and I woke up with cramping, back cramps, and brown spotting which is how the other two started. I called in to my doctors office but they are closed since it is Sunday. I am truly worried that its happening again. Is another miscarriage likely? I don’t even know what caused the other two because my doctor wouldn’t test, and since its the exact same timeline as before I’m worried.