I have a kitten who acts really strange when I take a shower. It starts as soon as I turn the water on in the shower. If I leave the door open while I take a shower, he meows at me and tries to get in but its too small to jump on the ledge. If the door is closed, he meows and claws underneath it. When I'm done showering and open the door I can't find him. And when I do he is usually hiding behind the fridge or another tight space. Acting scared or something. Why is he doing this? I'm worried as to why he acts like this.
Kitten making a fuss when you take a shower is entirely normal. You're doing something he doesn't understand and you aren't letting him participate. Even much older cats may want to supervise, or to jump in after you've out and investigate the heat and smells. Mine usually insist on trying to drink some of the water left in the bottom of the tub.
Hiding: Perhaps this is separation anxiety; the human has left him All Alone and isn't available to help if he gets into trouble, and he's young enough to still be nervous about that. Or this may just be a game; he has learned that after a shower your willing to play hide-and-seek. It's also possible that you come out of the shower smelling different than when you went in and the kitten isn't immediately convinced you're the same person; if so he'll figure it out over time.
I don't think there is any need to worry.
If they were completely predictable, they wouldn't be cats.