I Just got a CPAP machine

I had a sleep study done last week, that showed I had severe sleep apnea. Yesterday I got my CPAP machine, I was excited, and anxious for bedtime to come so I could try it. I did spend most of the night during my sleep study with a CPAP machine on, so I knew what to expect, but I really didn't expect to wake up as much as I did last night. How long does it take to get used to sleeping with the mask on. It's not uncomfortable, just different. During the study I didn't have the humidity added, that seems like it will take some time to get adjusted right, everything inside the mask was wet. Is it really helpful to have the humidity feature turned on, it seems like it would be less annoying with it off?
Just interested in hearing others experiences, I'm really looking forward to days when I am not exhausted when I get up in the morning!!
Deb