18 days late and lower right pain

I am currently 18 days late, I’ve never been more than three days late, ever. I don’t really have any symptoms at all for pregnancy or period. I had a tiny touch of nausea last weekend and threw up. I had a very little bit of spotting when wiping after sex last weekend as well. But since last night I keep getting these sharp twinges in my right lower abdomen. Just a sharp little stab and then it will subside and come back again.

I have taken a few pregnancy tests up to last weekend and all negative.

Thoughts? Anyone?