Definitely complain. Pet stores are great places to get supplies....but HORRRRRRIIIIIIBBBBBBLLLLLLLLEEEEEEEEEEEE places for training. The trainer wouldnt have been bad if he was young & knew what he was doing, but if he's young and has no earthly clue what the heck he's doing, he clearly shouldn't be there. Get out of that class and complain as soon as possible.