Uterus pain ?

So im cycle day 17 my ovia app said I was fertile last week through yesterday and my glow app says im fertile starting today ! But anyway I woke up and my uterus is killing me im real sore to the touch and my back is killing ( but this is nothing new I have severe back issues ) the sore tummy is what hurts ! Anything that would cause me to be so sore something I've never had before that I can remember ! I had a miscarriage in March and had to have a d and c and have been trying ever since !