There are a lot of factors to determine how your stay will be.
I do not think anyone has the same exact experience in hospital as others do.

I don't know about the hospital you are going to, but for me, the experience was like being in prison. (But I've never been in prison, so I cannot compare) My last stay, I was not locked in my door, but someone was in there watching me 24/7 even while I slept. So, there was a member of staff guarding my door at night. I was on 1:1 obvs so there was always someone watching me. I was also in the intensive treatment center (where all the "violent"/"high risk" patients go) for most of my stay, so I was under surveillance nearly the whole time. I had my own room and there was no bathroom in the room. There was only one bathroom in the ITC and it was locked, so I had to ask a member of staff every time I wanted to use it. And even when I was using the bathroom, there was always a member of staff listening to me from the other side of the door. There was also the issue of meds, since I had a history of hiding meds and not taking them, so I was constantly being threatened with injections.

So, in most hospitals though, they don't watch you as closely unless you're on 1:1, which you usually are for the first day or two while there but it's usually not that way for long. Usually.

Take care! I hope everything goes well!