I was playing Pokemon White. I talked to that old lady in the Icirrus city Pokemon center and she gave me Brick Break (TM 31) and I taught it to my seismitoad ( I made him forget Rain Dance). I went to the gym right after that.
When I battled in the gym, Brick Break, that have a 15 PP, had only 5 PP left. So, was it a glitch or it happens when you replace a move with a TM with more PP?