Trying to understand

Sunday

So I’m 15 days late I’m so confused. I’ve been having full breast I had this sharp pain in my left hip/back buttock area if that makes sense.. I’ve been having these weird cramps nothing like period cramps but cramps. Then on 8/29/18. I had this inner thigh cramp on my right side, I almost passed out from the cramp it was hurting so bad. So now I’ve checked my BBT and it was 97.9.I hadn’t moved or anything thing 8/31/18 was the very 1st time I did this.. And I did it before I got out of bed I didn’t move much at lol so can someone explain to me how high the BBT is supposed to be if you are pregnant vs when your ovulating and ETC....