How bad was the injury?
Did the foot get hurt?
Did you add guards to your PH
's to prevent this from happening again?
Whats your lighting?
What kind of Anenome did you get?
What size Tank?
5 week old tank is not a mature tank, you should have waited until the tank was mature (12 months). These are not hardy creature, if the foot is hurt it may not be able to attatch itself to a rock and it may take days for this creature to find a spot that is comfortable.