Hi thanks for contacting HCM...
Noted you have 
acid reflux and 
shoulder surgery in past with just now having dyspnea on activity...
First rule out anemia as it can lead dyspnea on exertion...
For that HB and PCV estimation done...
If needed iron tablet given......
Second do you have 
hypertension ?? Cardiac history??
As early 
heart failure case can lead dyspnea with edema feet.
Rule it out by ECG OR ECHO.
If still problem not detected rule out respiratory causes by chest x ray and pulmonary function test....
For 
hiatus hernia induce relux take omeprazole like drug that you are taking.
Head elevation while sleeping.
Immediately after taking meal dont take sleep.
Avoid excess spicy and fatty food.
Excess coffe , chocolate like food avoided that relax LES.
Take care...
Dr.Parth