Hey Kim - just to be safe _ I think I would pour the new litter into something else and just give the box an extra good rinse and wipe out and then refill with the litter - maybe some scent in the cleaner is bothering him. Can't hurt! Pee doesn't take as long as pooping (requires more serious concentration ya know!) and maybe the scent is annoying him?? Does not really sound worrisome though - sense he IS getting in the box, clawing the litter, etc. Maybe he just over reached his mark a bit.