Post period pelvic pain?

My period finished on 18.05

Last night on the 20.05

I experienced a use severe pinching in my lower abdomen ? It wasn't a typical period cramp as I usually don't get very bad cramping ? Could it be ovulation cramping that early ?

I'm having trouble tracking ovulation?

I had the mirena coil in for 5 years and I've been having fairly regular periods since I came off but they are very light in flow,very dark in colour and only last 2-3 days ?

Any advise would be great