I’m a relatively.new shrimp owner so can’t say anything for sure. I’ve done a lot of reading up and browsing of this subreddit though so I have a few guesses to posit.
I’ve read that first time mothers often prematurely molt / drop eggs. I would imagine it’s possible your mother did that and dropped some of the surplus eggs and the early molt left her coloration a bit different.
Hopefully she’ll still have some shrimplets and so long as your conditions remain favourable there will be more in no time.
The other guess I have is that you said you started feeding Bacter ae, which is smart- but I’ve also read that for small tanks you feed like a pin drop at a time. If you’re feeding more it could cause a spike (but your tests are fine) but also I’ve read it can cause a lot of oxygen consumption. This could cause some stress- so just double check you’re not giving too much Bacter ae
NoNameAnonymousAlex 
I’m a relatively.new shrimp owner so can’t say anything for sure. I’ve done a lot of reading up and browsing of this subreddit though so I have a few guesses to posit.
I’ve read that first time mothers often prematurely molt / drop eggs. I would imagine it’s possible your mother did that and dropped some of the surplus eggs and the early molt left her coloration a bit different.
Hopefully she’ll still have some shrimplets and so long as your conditions remain favourable there will be more in no time.
The other guess I have is that you said you started feeding Bacter ae, which is smart- but I’ve also read that for small tanks you feed like a pin drop at a time. If you’re feeding more it could cause a spike (but your tests are fine) but also I’ve read it can cause a lot of oxygen consumption. This could cause some stress- so just double check you’re not giving too much Bacter ae
[before pic of her](https://www.reddit.com/r/shrimptank/s/RSLyj5vt38)