I would Suggest You wait for 30-45 days and go for a Recoloring of ur Tattoo... it happens sometime that Excess Plasma output can Fade the Tattoo much.. But there is nothing to worry abt...
As soon as you notice your tattoo starting to fade, then it might be time for a touch-up. When you initially get your tattoo done, ask the artist if they have any deals on free or discounted touch-ups after you are tattooed.
A good tattoo lose few colour. If your tattoo have lost colour isn't made with good colour. You gotta go to another most skilled tattoo artist to recolor you tattoo
As soon as you have stopped pealing in the area you should be fully healed. It's always a good idea to wait 2 weeks to insure that it has been fully healed before you can recolor it. Just make sure you are not still in the healing process.