Big hugs to you LS2! It's a tough spot you're in. I was there about 10 years ago. I had *wrecked* my credit in grad school by failing to file deferment papers for my federal student loans. It was awful. Embarassing. I hated admitting to people what I had done.
Those people at stores when they ask you - "Would you like to apply for a store charge?" ... made me want to vomit and cry because I knew I would never be approved.
But... life goes on. You learn from this and grow. It's not going to be easy, but nothing worthwhile is. One day at a time, you pay your bills on time, you build your credit and 4-5 years from now you can look back and be proud of what you accomplished.
Have faith that your HP will take care of you. Keep searching for a place and don't be afraid to ask for help. Do you have friends that can help you out in the meantime?