So I started using 2L of O2 at night on Tuesday and every night since I've slept like crap. I'm up constantly coughing and moving trying to get comfortable. The first two days I woke up with no headache but this morning I have a headache and some serious sinus congestion. At this point I'm annoyed because I was sleeping better without it. Right now I'm pretty much getting up every two hours. Anybody else have a similar problem?