I'm sorry about your past suicide attempt and that you're feeling so low now. You haven't taken any action this time and you don't want to, which is good, so they'll ask you if you can keep yourself safe which it sounds like you can and that generally means no hospital.
For right now phone, text or email Samaritans for a chance to express yourself, your feelings, a shoulder to cry on if that's all you want. They're non judgemental, and you don't have to give your name or address. You can safely say anything to them.
GP emergency appointment tomorrow. Don't be fobbed off by reception desk you need to speak to the GP. They'll probably offer you antidepressants, which might help with the intrusive thoughts as well as your general mood. The GP needs to know about the intrusive thoughts because there might be one type that's better than another for combatting these.
Contact a mental health charity in your area to see if there's any other help available.
If you can't sleep tonight try to do restful things instead, it still helps your body to rest a bit. Calming music, comedy shows on DVD, reading, write in your journal if you have one, anything to distract you from the thoughts. Don't complicate it, if you fall asleep on the sofa that's fine. You just need some rest tonight. Do what you can and don't worry about what you can't do.