If you drink hard alcohol, frequently, and lots of it, for over a period of time, you likely will have developed an ulcer in your esophagus. This is kinda like a sore that is there, and sometimes gets aggravated (especially when stressed ) and really hurts bad..and other times doesn't hurt at all. Acid reflux is often associated with this, as well as stomach ulcers.
IF YOU HAVE PAIN WHEN YOU DRINK ALCOHOL YOU NEED TO QUIT DRINKING. THE DAMAGE TO YOUR BODY WILL CONTINUE GETTING WORSE AND THE PAIN WILL INCREASE. YOU MAY SUFFER FROM SEIZURES, BLACKOUTS, LIVER DAMAGE, AND EVENTUALLY LIVER FAILURE ... AND DEATH.