Implantation cramps ??

I'll get straight to the point, month of November I had lots of sex with my man on and around my fertile window & ovulation date.

As of th past 2 or 3 days including today I have been very crampy in my lower abdomen but mainly my lower back. ALMOST like pms cramps but not constant or as severe. It comes and goes thru the day.

No other symptoms really besides my right breast is a bit sore.

ADVICE PLEASE.. I know I need to test but every negative is discouraging. So I'm extra cautious on just testing.