Period 9 days late after first IVF cycle

My period is always regular within 1 -2 days of when I expect it. Now it is 9 days late.
We did our first round of IVF in January/February and after egg regrieval nothing fertilized. I had my period about 2 weeks after that.
I've stated taking CoQ10 and some vitamins but that wouldn't make my period irregular would it?
Has this happened to anyone else?