What Causes Cough, Pain In The Ribs And Sleeplessness After Using CPAP Machine?

I just got put on a Cpap machine for sleep apnea and since I've been using the machine I have developed a bad cough with clear phlegm and serious rib pain on the right side of my body I have more trouble sleeping nowthen what I did before I was told I had sleep apnea what can I do for this .