Why no cramps this month?

Ang

Hi ladies, I always always get cramps every single month that range from mild to painful. I thought I was pregnant this month I got zero cramps and took 2 tests both were negative. Then at work I got my period a day later than usual. Any particular worrisome reason(s) why I didn't get any cramps? I didn't do anything different, I didn't change my diet, my exercise and everything is the same, thanks 😊