My new kitten - Sick?

[Black_Twilight]

Hello everyone. A while ago, a kitten would come around my boyfriend's house everyday to eat and sleep. It was a male kitten, all black and very beautiful. The kitten was in rough shape. He had a tick in his ear, his fur was all scruffy, his eye's watering and he seemed very cold and lonely. My boyfriend gave this kitten to me, and i had taken the tick out, bathed him, fed him and gave him everything a little kitten could ever need and want.

After a while, i started noticing that he isn't playful at all, for a 5 month old kitten. He isn't even active to the least! I've tried everything i could think of. I have closed my bedroom door, and put him on the floor.. but he would only walk far enough to get to a place he could lay down and sleep. (Like a chair, bed, couch, ect..) He seem's to walk okay, but just doesn't like to be active.

Also, i have been feeding him dry cat food. It seemed to be fine for a while. But this morning, i noticed that Twilight had vomited beside his litter box. What is wrong with him? Is he sick? Does he need medical attention asap?

I adopted this little guy the day he came to me. I couldn't put him back out, and i couldn't give him up! I hope someone can help me, as he's become a big part of me now.

Thank you.