Clomid and Period starting very early

I was given provera to induce a period then took clomid day 5-9 50 mg. Day 17 of my cycle I woke up to extreme bloating, nausea, and vaginal bleeding. Bleeding has increased to period flow. I have not gotten a positive opk. Dr wants to get an ultrasound but it won’t be seen for almost two weeks, still supposed to get a progesterone check on cd 21. Has anyone had this happen to them before? I have no idea if this was caused by the clomid or my period is coming back (I have pcos)