Uterine twitches

Im feeling what i can only describe as “twitches” like a muscle spasm or eye twitch but in my uterus. I had my period on August 2 and then on August 24 i started spotting ( i thought it was my period because my periods have been rather light) and then again a few days later. I should have gotten my period around September 2nd but i still haven’t. Could this be an early sign of pregnancy? I can’t imagine i would feel anything this early but i guess you never know.

Ps i took a pregnancy test 5 days ago and it was negative