Constant cramping

I posted on here a few days ago saying I was 6/7 dpo and have had cramping and backaches. Well today I am 8/9 dpo and I still have cramps and lower back aches. They are consistent and only stop for maybe 15 minutes then are back for hours.... is this a good sign?!

I usually get cramps the day before my before and the day of then I don’t cramp until ovulation. I have taken ovulation tests and they are negative.

Is constant cramping a sign of maybe implantation and pregnancy?!