Still nursing my toddler & trying to conceive

Is anyone in the same boat as me? I'm working on not nursing anymore because of several things I've heard and because my daughter is already 17 months.

I'm trying to conceive and only 1 nipple has been extremely sensitive to the touch. Not sure if it can be due to nursing or possible pregnancy. It hasn't hurt this bad at all. Period is due 2/04

I know it's early but I tested today and got a negative