Question:

Why does my nose close up and tingle when I sing for long periods of time? Does singing affect your sinuses? Am I not breathing right?

Answer:

Yes, the vibrations from singing do affect the sinuses. The stimulation can cause congestion to be released into the nasal passages. It is not likely that breathing has much to do with it, unless you are forcing too much air into the tone. You might try using a sinus rinse (a simple saline solution) with a neti pot as well as kapalabhati breathing from the yoga traditions. If you do a google search you can get free instructions for both. These will clear the sinuses before you sing.