6dpo with strong cramping???

dani • Married 1 year...TTC baby #1
I am on my third round of clomid (150mg this time) and currently 6dpo. For the past two days, I have had AF-like cramps which do not get any better after going to the bathroom (so I know they aren't related to that). My nipples are a little sore but this cramping is painful. I know I am not expecting AF this early (last cycle I didn't even get it on my own and had to start progesterone around cd45), so any idea what this could be? I would really appreciate any advice at all!