Okay, I'm typing up this mini-essay for two specific reasons, I want to know what is wrong with me, and what causes it.

I'm a 18 year old male, and I've been plagued with some type of mental issue. Ill keep this as short as possible, I spent two months locked in my room, I spoke to noone. I said maybe 20 words to my family during that time, and I only left my room if i had to use the bathroom, I ate only 10 days out of the two months i spent in my room and I did almost nothing the entire time in there, I literally did absolutely nothing. I started reading a book but couldn't keep myself interested, I spent one entire day listening to my entire music library, and every other day I was either just laying in bed or lost in thought. (cant even remember what i might have been thinking about) Now its been about a week and other than the fact that I can barely get enough sleep, I feel fine. I don't think that it was any kind of depression because nothing happened that would have caused me to become depressed. It was as if one day someone turned me off. Now I feel completely normal.. but i still feel like somethings wrong, in fact i know it, I barely eat and i dont get nearly as much sleep as i should. I'm also scared that something like this may happen again because it's happened before, just not this long and as intense.

Any answers?