So, it takes a bit of time for hormones to get going again. First, I'm really sorry about your miscarriage! That is always so hard. But it can take 7 or so weeks to get a period again after a miscarriage. It's been a bit longer for you though . . . Your hormones sound out of sync. I'd see your ob/gyn to do some blood work and see what is going on. Three months is a long time to go without a period. I had long cycles like that with a period every 3 to 4 months for about a year and a half and was diagnosed at that time with hypothyroidism and a natural too much production of estrogen. Blood work revealed both of those. Let us know if you can get in to see your doctor!
I am so sorry for the loss of your baby. I have two angel babies, so I know the stress and discouragement that can come from it. The first was natural but the second I had to get a D&C due to clotting. My thoughts are with you.
As for the lack of menstruation, the normal range for a persons' hormones, after a miscarriage, to sync can range from 4 to even 12 weeks. Some doctors will tell you to wait the 12 weeks and see since your body went thru such an ordeal. Since you are at that point, it could be numerous things. Your body may just need more time for your body to recover and hormones regulate. You could have a small clot left over (which is not as bad as it sounds). I had one before...Your Dr. would have a treatment plan if that would be the case. Another reason could be that you are pregnant. If you have regained sexual activity since the miscarriage, have you taken a pregnancy test yet? That usually is the first thing the Dr. will test. I would keep to your original plan of going to see your Dr. if you do not have an answer on your own by the end of the month. I hope you get the answers you need. Good Luck!