Sounds like you may have a sleep breathing disorder such as sleep apnea. What did you sleep study results say? You may want to do a trial with a cpap machine to see if this may help you, probably with a full face mask since you have difficulty breathing through your nose. I suggest posting on the sleep breathing forum where you can ask Dr. Steven Park your questions
Visit an ent or allergist, and have a pulmonary function test. You may be developing Asthma, from sinus issues.
Chest discomfort & shortness of breath, can be caused by many different disorders, acid reflux, Asthma, costocondritis, etc.....
It's best to address, your concerns with an ent/allergist or doctor, and allow them to do proper testing, to eleviate any abnormality.
Good luck !!!!