i really sympathise with you-i had a very similar experience in a UK ward.
i was locked up in an acute mental ward for a very bad round of paranoid schizophrenia,they set the alarm off regulary and i was jumped on constantly.
i was highly sedated with meds and i was locked up with my own nurse sat in the room,they coudnt cope with me and i was transfered to a acute learning [intelectual] disability hospital miles away. i was pinned down by the police for twenty hours in total.
the LD hospital was worse,i now suffer from severe sciatica thanks to all the restraint.

i hope your experience isnt as rough as mine, you need to be well and they will let you out in the near future,i was in hospital for four months because of my behavior.
if your not well,dont pretend to be well-you deserve the support.

if you feel stable enough,ask for a section 17 [i think thats what it was called] its where you can go out, you coud arrange a visit to a shop,a burger bar etc,im assuming youve been sectioned though if not,you dont need a section 17.
a nurse or two nurses [depending on your risk] may have to go with you.