I have been diagnosed with sleep apnea and was prescribed a CPAP. How did I get used to this thing?

I have used the machine for about a week, but can not stay asleep with it on for very long? How long does it take to adjust to these things. I am determined to use it.

Is there any prescribed sleeping medication that can be used if you have obstructive sleep apnea?

I use bi-pap, but am still unable to sleep. I thought I read somewhere that there is a prescription sleeping pill that is safe for peopel with obstuctive sleep apnea to use.