This might sound counter-intuitive, but don't drink water before bed. Drink it when you wake up. Water wakes you up, so not only will you fall asleep faster, but you know, no pee

my back hurts enough to wake me up

I'm not gonna tell you to hit the gym, but DEFINITELY put a pillow under your knees. 1 week of pillow under knee sleeping, you won't go back to without it

If your white noise isn't sufficient, you could also try "brown noise" - same thing, but lower pitch. Some people prefer it. Also regarding the bird, I can't help you for that, but make sure your blinds are closed and it's dark in the room (or otherwise try sleeping with a shirt covering your eyes). Light sensitivity is big for some people (including me)