I've been to 3, so I'm sure there will be others who can answer with more experience, but I'll give a few answers based on my experience.

As far as how mentally ill you have to be to be admitted, I think it depends on if you're voluntarily admitting yourself or being involuntarily admitted. From what I understand it's difficult to get involuntarily admitted unless you are truly suicidal or homicidal. If one wants to admit himself/herself because one feels like he/she need to be there, it's seemed to me that mental health professionals are usually open to working with that option to help someone improve.

Once I was locked in a room for many hours by myself upon admission while they were waiting for a bed for me, but I don't think it was padded. I honestly can't remember. There was nothing in it except a bed, though, and that was pretty horrible.

What you do inpatient depends on the place, as well. I think most places have individual therapy sessions and/or group sessions that go on throughout the day, and of course there are meals. A lot of times people just sleep in between these activities. Especially if you're on new drugs, at least in my experience, it can make you really sleepy. Some places have activities like board games, pet therapy, and group activities planned for fun. Other places just have a big, boring room with a TV.

According to my experience, they can forcibly inject you with medication. I got too worked up about something and they wanted to calm me down. I don't know if they do in other cases or what reasons they would have. They didn't force me to take my oral medications, though.

Some places allow you to keep your phone and others don't.

The experience of being around other patients will vary. Sometimes they're friendly, sometimes they're not. Some scream or moan and cause a lot of commotion but a lot of the time it's quiet and there's none of that going on.

I didn't feel that my psych stays helped me, but my medical paperwork says I improved, so it's possible that my treatment team saw improvements I couldn't see at the time.

Hope that perspective helps a little…