Hi, 

My little girl (10 months old) has stopped breastfeeding on my left breast because she mostly has bottles and when I feed her now it's during the night and she naturally navigates towards the other breast.

anyway - the breast I've stopped breastfeeding her from (for 1-2 months) is a different colour around the areola. It's basically "Stayed" the same darkened colour as it changed when I was pregnant. 
 

ive also noticed mainly that the nipple/skin around the nipple is pulling in and making it much more noticeably retracted/ inverted than the other breast that I'm still feeding on.

I went to the doctors before Xmas about the colour difference and she said she wasn't concerned about it.

but I did feel the pulling in as you call it was getting worse so made an appointment this week and she said she did see what I meant and it definitely did need checked out but she didn't think it was anything sinister as she couldn't feel a lump??

x