I was diagnosed nearly a year ago and I must admit it took me time to adjust to my CPAP machine and mask. Now I take a sleep aid (2 tablets; Walmart brand name) before I retire and I sleep like a baby. My machine has been set to give me 10 minutes before I receive full pressure. I am usually asleep within that 10 minute time period. If not, I hit the button (like the snooze button on your alarm clock) and I get an additional 10 minutes.
Give it time and if it is not working for you, check with your doctor or medical supply company to see that it is the right mask for you, and that it is properly fitted to your face. Good luck!