What is wrong with my kitten?

You should take him to the vet. It would be much better instead of asking the Yahoo! Answers Community.

And all of the answers so far say to take him to a vet.

Poor thing, I don't know what it is, but it sure doesn't sound like a hairball. Maybe he ate something really bad (old, poisoned) You should definitely take it to the vet.

usually when cats are sick or injured they will instinctively hide under the bed or couch.. somewhere were predators can't get him since he can't defend himself. Your kitty might be doing that, and if he isn't that means that he is even too sick for it. Not a good sign.

Take him to the vet!!!

hairballs rarely cause lethargy, appetite loss, and malaise, i'm thinking he ingested something bad: poison, toxic plants, spoiled food, something like that and its causing him stomach to hurt and him to vomit, and because he is a kitten, you have waited too long to take him to the vets, kitten should not go without proper nourishment for over 36 hours and you have waited four days, its time to get him to the vet, if he is vomiting, that's just what you can do to help, get him to vomit more, but don't suggest this, i HIGHLY suggest a vet visit and SOON, but if you cant afford it right now/one isn't available, use his bodies reaction to your advantage

There doesn't seem to be any easy home remedy. You absolutely must see the vet as soon as possible. This is not normal. You cat is unwell.

i would buy a kitten feeding kit and if that doesn't work i would take him/her to a vet

sometimes the mother will reject a kitten... unless its an older kitten seperated from its mother.... that might also be the problem

it sems like in pain to me ,take itto the vet,u dnt wanna regret it later on if its something serious

The best thing to do was to take him the vets.It may be nothing or it may be something big.Its best to make sure.

i think it is probably best that you take it to the vets

I would be concerned that he isn't eating. Please take him to the vet to find out why.