Urge for frequent deep breaths. Urge.

I am facing this condition from last 8-10 months. I constantly feel this urge to take deep breaths and if I avoid taking it, I feel very uncomfortable may be something close to feeling shortness of breath..however one small sigh is enough, but again after few mins I feel the same urge.this doesn't happen at any particular time or doesn't have any specific pattern.. but mostly I feel this while having food. Or also when just sitting in a relaxed position.my O2 levels are normal.. also in the month of Jan I got a spirometry test done on my Dr.'s advice which also came out normal However this still continues..I also experience a blocked nasal passage sometimes mostly in the morning after waking up with little sticky mucus at the back of my nose..I also experience palpitations sometimes while in deep sleep.. this bothers me..kindly help