Give him a few weeks. I think my vet told me it takes about 4 weeks for the hormones to completely leave their systems. My vet also said that males should not lift their legs to pee and wouldn't have the urge to hump things (like toys)-but that was not the case for my Amos. I had him neutered as early as I possibly could and he still lifts his leg to pee and has a stuffed animal that he gets rather friendly with. He doesn't mark in the house, but he will stop about 10 times and pee if we go on a walk. Just be patient, he'll come around.
