1-800-273-TALK (8255)
I'd recommend calling the suicide hotline to get some emotional support, and better answers to your Q's. I don't know where you live ~ so it's a little tough for me to advise that you go to wherever.
I don't know national laws, but I'm pretty sure that all hospitals have to take a person who's suicidal. That doesn't mean that they have to keep you there though. They may be too full to keep you, and then send you to another hospital that has availability at that time. It's kind of tricky.
It may be determined that you would do best in a long-term residential halfway house, one that can hopefully help put you into a better state of mind. Or, maybe you just need a few days to a week of medication tweaks to get you feeling better. A lot of unknowns!
If you are seriously in need of assistance, please do call the number above. 24/7, they are always there waiting to help!

I hope that you get the answers that you're searching for and the help that you need. Very best wishes to you!