Cat hasn't ate/is hiding?

Hi everyone :)

So a friend of mine would always feed cats that would come to her yard. She said she had gotten them taken to the vet and got their shots. Anyway, idk if this is a stray or feral cat but she/he hasn't made any noise since I brought her home. It's been a day and maybe I'm being impatient (I'm an amature never owned a cat) is this normal behavior? The cat hasn't ate, meowed or drank anything and it had been hiding under the bathroom sink since I brought her in. I fell asleep and now just woke up to find her gone somewhere. ( I live in an apartment) should I just give her time?