HI, A few years ago I started waking up with a sinus headache in the morning. No noticeable congestion and the headache would go away once I got up (usually an hour later.)This happened one of twice a month. Last year I started having them one a week and now it’s almost every day. They seem to occur when I sleep on my left side which I try to avoid doing for any length of time. Now it doesn’t seem to matter to much as even a ½ hour on my left side produces of sleeping my back produces the same head ach. I don’t have a cold or any sinus drainage and feel fine once I’ve been upright for a few hours.