Hello, this is Dr yash 
I have gone through your question. 
First of all try to reduce or stop 
smoking, because smoking is also the risk factor for 
acid reflux. 
Try to eat little food, don't eat spicy,  fatty and too much of food in a single time. 
Have your dinner 2 hr before going to the bed. 
Dont take too much water with food. 
Acid reflux occur due to decrease in lower esophageal Sphincter tone. 
To daignosis this, you have to go for upper GI 
endoscopy,  24 hr PH monitoring,  lower esophageal pressure tone. 
Till then you can have some 
antacid like ( syrup mucain gel 5 ml thrice a day before food and tab PAN-d twice daily before food. 
I think I have answered your question. 
Thanks