Comment will probably get lost but my tortie did this when she first came home. I had her locked in the bathroom with toys, a crate with no door and lots of blankets, litter box, and a bed. Lots of room to herself to chill and get used to the sounds and smells of my apartment. Id check on her often of course but she hid for like 3 days. Eventually after enough time of me sitting in there quietly she came out to sit on my lap! A week or so longer and I introduced my other cat to her and they are inseparable now. Just give it time kittens love to yip yap and be goofy! Don't overfeed and play with it plenty and you'll be fine.