Nipples hurts

My nipples hurt a lot since yesterday, the last time I felt this pain I was pregnant, my son is 8 years old for my 4 year old girl pregnancy I never felt like that, before my period my nipples have never hurt. I have my tubes tied that I don't think is a pregnancy, my period is supposed to arrive in 7 days. Other symptoms that I have are back pain and cramps.

Pre-menstrual symptoms can change? since this has never been a pre-menstrual symptom but it has been a pregnancy symptoms, at least in my case.