Oh I hope this is a good sign for you. I got my BFP last month. And 11-13DPO I had very strong AF cramps that would come and go. On 13 DPO had a blob of red CM, and was very disspointed bec I was sure AF was here. But there has been no more or it for the next 3 days and I tested BFP.
I never imagined that BPF can feel so much like AF.
Good Luck.
I had that but mine was because I was two days away from af and for some reason after ovo the menstrual cycle cramps are stronger. Hopefully your case is different but hang in there and heating pad will do wonders.