I needed the NyQuil to sleep myself, but that is when it dried up my sinuses and the sinus headaches started. Lasted over a week. Overall, I did better without it. Always a trade off.
Gotta stay hydrated - lots of water... One shot of regular nyquil before bed and I was good for 6+ uninterrupted hours sleep. On the worst sinus days I'd do a shot of Dayquil too, but that has more phenyl-whatever in it and can make me edgy.