I've had the breast tenderness. It's always been related to my cycle and goes away when I start. For some reason I can go months and not have it and then have a few months where a week or two before I start they feel swollen and tender.
How old are you? I am 51 and skipped my first period ever (other than my 3 pregnancies) in Feb. of this year. After 60 days I had one and then almost immediately after I quit flowing (approx. 5 days) I got the tender breasts. Along with it, though, was the exact thing you explained about the sensitive nipples. The only other time I have experienced that was when I was pregnant with my second child. And I know I'm NOT pregnant because right now I'm starting another period after only 15 days! UGH!!!
The only good thing is the soreness and tenderness has almost completely eased up. In its place I am now getting cramps.
I Know it's all hormones gone wacko and good ole perimenopause. I'm sure for you it's nothing to worry about either.