Constant acidity, dry cough, burning in throat+chest when exercising, breathing trouble. Is my sleep apnea causing this or is it acidity causing apnea?

Chicken & egg. There is an association between acid reflux and sleep apnea. There is no proof that reflux leads to sleep apnea (or vice-versa) but the association between the two has been shown repeatedly. You need optimal treatment of BOTH conditions to feel well again, so TTYD about a sleep study with a CPAP mask and Prilosec or other acid blocker. Hope this helps. Thanks 4 trusting HealthTap w/ your question.
Symptoms. Your symptoms may be due gastroesophageal reflux.