Awful first night experience

I just got my trial unit yesterday, a Resmed, and we went over how to use it. Well, it came time for sleep and I set it up the best I could given the space I had. It was awful. Once strapped in, it would constantly blow air at all times. I did not like the feeling that I had to have my mouth shut or it would pass air nosily through my mouth. This must be worse than snoring if anyone else in the room could hear, I bet. I adjusted the settings and I think I basically turned it off. After about an hour and a half of struggling to breathe fully through the mask (I have the "pillow" style that sticks to the nose) I took some melatonin. 30 minutes later of more tossing and turning, I took off the mask and took another pill. I don't think I felt like I fully fell asleep and I feel so sleep deprived this morning. Just an awful first time. I was really hoping to feel that "best rested sleep" feeling everyone described. I'll have to follow up with my provider to see what I did wrong.

Update: Night 2 went much better! See post for details.