I just noticed a dark ring around my areola?

Sammy

I've never noticed this before. yesterday it was not there and this afternoon, I looked and saw a dark ring around my areola. not thick, pretty thin but clearly darker than the rest of my nipple.

I've also been very stuffed lately and had barely an appetite.... it has caused me to lose 5 pounds in the last week. I'm not throwing up however, I feel nauseous and full all the time.

what is going on?