Painful Nipples Early Pregnancy Sign?

I need some early pregnancy advice! I have a 1 year old girl now and my fiancé and I haven’t been preventing but haven’t been actively trying to conceive. I’m supposed to get my period sometime next week, but the past week, I had lower back pain for 2 days, I’ve been super moody and cranky, and now all day yesterday and today my nipples have been extremely sore. I’m still nursing my 1 year old and I’m shocked at how sore my nipples are. I took a test 2 days ago and it was negative. Im wondering if I’m pregnant and these aren’t early period signs and it was just too soon to test. I’ve had 2 post partum periods and neither time did my nipples hurt. What do you Mammas think? Advice for TTC #2??