Cleaner Shrimp is sick

[sir sqarepants]

My cleaner shrimp which I have had for almost a year now has been twitching from side to side rather than swaying like it used to do. Also, the black part underneath the skeleton where it's stomach is at is now pale green.
I don't know if this has anything to do with it, but the shrimp just molted two days before this started happening.
Anybody know what's wrong and how to treat it.

 

[spongbob squarepants]

only one. water levles are near perfect. seems to still be the same.