Hi , i just got my 1st ball python couple days ago . but i noticed he always stays in his hide,like i thik 70% of the time. is it normal?

And i 'm using a tub . i Drilled holes on both sides. The 1st day i put him in . i was still fixing the hide,before i put the hide into the tub , he keep moving around and tries to "push" the top cover . is it not enuff air ? coz i have 7 hole drilled on each length.