Keep telling yourself in your head that you will be dreaming soon, dont drink too much caffiene or it will be harder to fall back asleep, only a little. Get as comfortable and relaxed as you can, dont be afrain to switch positions and roll over, your arms falling asleep could just be that they went numb cause you hadn't moved them in a while.... You wont be able to fall asleep if you are uncomfortable.. Relax, have a good breathing technique, get all the "kinks" out of your muscles and joints, stretch maybe before you go back to bed.. I like to have a lil "white noise" while i'm attempting to wild, such as a fan of some sort or the A/C blowing in the background, it kind of lulls me to sleep. Keep at it though, it seems like you are close and have the right amount of dedication to succeed, rememeber, stay positive!!!! If you think you can, then you probably will.