Meh. I don't feel right.

Cd 20, not sure how many dpo. I went to the store to get something to munch on and this car is parked way too close and I can't get out of my car and I just started balling yelling at the guy to move because I can't get out of my car! 😳 not like me at all, even if I was PMSing. Since Monday I've had just the most full/pulling feeling in my lower abdomen. I also had what I thought to be implantation blessing on Monday. But it was just once when I went to the bathroom in the morning so idk. I took a dollar store cheapy pregnancy test this morning and it was negative. Anyone else had anything like this and been pregnant? Or am I over thinking everything?