question: It s been 3 weeks...I sleep for approx 40 mins then wake up gasping for air and having an anxiety attack. I HAVE TO get up and walk around. Once I calm down I fall back asleep...for about 40 min...then it all happens again and again all night. I m sleep deprived and exhausted. I have a CPAP. Doesn t help. I ve tried melatonin...doesn t help.