I used to have trouble sleeping, but now I have a routine. If you keep thinking about sh*t while youre in bed, you'll never fall asleep fast. You need to go to bed and just close your eyes, relax, don't think of anything exciting, sad, bad, scary, interesting, nerve racking or problematic, just sleep. It's the thinking that keeps you up, one thing leads to another and before you know it you've been thinking for a good few hours, then when you get so tired that you can't even find the energy to think, you fall asleep, give your brain a rest, don't think.
I have an electric heater on so when I wake up it's nice and warm, and it's quite a loud sounding one too because it blows out hot air, but there's something about sleeping in the warmth of my bed, with a heater buzzing that I just drop off too.