Cytotec may not be working?

I was prescribed the oral version of Cytotec for my Mmc, lost baby at 6w4d, and I’m afraid it may not be working. I have 3 doses to take every 12 hours. The pills are 200 mcg tablets. I took the first round, 4 pills, last night at 10:30. I woke up a few times with bad cramps and diarrhea. I thought for sure something would happen but nothing did. I took the second set at 10:30am today and now waiting. So far no cramps or anything. I feel a bit lightheaded, but not sure if it’s my nerves or the medication. I have had other friends go through the same thing and they had been given the vaginal form which seemed to work within a few hours. Has anyone had a similar experience? I was thinking of calling my OB for vaginal pills for the 3rd round, but had read that for women with Previous Csections it could cause uterine ruptures. Very confused and unsure of what to do. I’m terrified of needing surgery if this doesn’t work. I would welcome any feedback from you ladies.