Yes, this is excellent news for you. It means you are on your way.

The changes in your nipples and areolas is due to the phyto-estrogenic hormones taking effect. It is not uncommon for areolas to change color during development. As to the skin sag no more. This is even better news. It means that you have fat and tissue development going on underneath the skin. Most likely you may not be able to tell a lot of differance using a measuring tape. That is why we say take pictures. Changes can occur that we simply do not pick up on. They take place slowly. A filling out in the chest area. Have you been feeling any aches and pains? Soreness, maybe on the side of your chest. Between the nipple and arm pit? Don't worry if you haven't. They may be just around the corner. Have you posted your program? Inquirng minds want to know.

Don't worry about the spelling. I am not that good eigther.
Good journey
Andy