I had almost this exact scenario happen to me. I told a college counselor that I was having suicidal thoughts and she freaked out and had me involuntarily committed when all I wanted to do was talk to someone.

I wasn't held for a minimum amount of time but the scariest part was that they hold you against your will with no set exit date. So you have to essentially fake getting better so that they free you. Meanwhile you're completely cut off from the rest of the world so your friends and family may have no idea what happened to you, you may lose your job. For me this was right before finals so I wasn't able to study (gee that's sure stressful to an already stressed college senior).

Ontop of all that I actually saw a doctor maybe twice in the week that I was there for a total of 10 minutes. Cost my family ~5,000 dollars in insurance deductible (wow more stress huh). And all I got out of it was a bottle of prozak.

Our mental health system is a fucking joke. I scoff any time I see people on facebook or twitter generically posting "go get help" when it comes to suicide. FUCK THAT. I current see a therapist and she's amazing but I never once mentioned my thoughts of suicide when i was having them and I don't think I ever will because the way the laws are set up it's a liability for them to not call the police on you. The entire thing is fucked and the stigma of being committed is equally horrible in making you feel broken.

Oh and the roommate thing 100%. I had a shared bathroom with another room and had a guy walk in on me. My actual roommate was a basically comatose older guy who never left bed. I saw a patient stomp on a live mouse. Fortunately there was a couple people there who were cool to talk to and kept me sane. And the kicker through all of it I was held longer than a guy who ACTUALLY SHOT HIMSELF IN THE HEAD.