I noticed that the first day i had him he was very active. after that he hasnt left his hide spot in the past two days from what i've seen. is that normal?
Very much normal Balls love to hide its "their thing"


how often should i clean the cage and replace bedding?
Depending on the bedding. something like eco earth or aspen should be spot clean every day and replaced once every week or two depending on how soiled it gets.

If your using paper then every week without fail and spot cleaned every day.


also i wanted to take my bp to a vet. to get sexed and checked out for any health problems. Even though it seems very healthy by the way he constantly flicks his tongue and was very curious. his vents also looked clean and their weren't any scars or bumps along his body. i was wondering if its okay to take it to any vet or should i call somewhere that specializes in reptiles?
sounds over all like a happy healthy Ball Python. you can take it to a vet just make sure they deal with exotics.

Welcome to the site and best of luck with your new buddy.