I've always hated hospitals, they turn on my paranoid mode.
I would never even stay in the nurses office at school for more than a few minutes when ever I got sent down there for sleeping in class (yeah...) because I keep thinking there are tons of airborne viruses. Hell, I used to even hold my breath when I passed it, so I hate when I'm forced to go into a hospital for long periods of time because obviously I can't not breath the whole time.
Thankfully I've never had to stay at one for more than a day, a part from when I was born, of course. Only other time I had to stay for a while was when I broke my arm when I was three.