acid reflux
You might just have plain old acid reflux. I had it for years before I started body- building. The coffee, chocolate, (caffeine), spicy foods, etc... loosened the Lower Esophageal Sphincter muscle, and the intense stress in my life added to the problem. Was in ER once because I got so sick. Then gorging of food pushed on the already loose muscle. Prescribed medications did not work either. They were a joke.
Decreased coffee, chocolate and eating numerous small meals throughout the day, instead of three huge meals ultimately solved the issue. Unfortunately, physical activity does cause acid reflux. I would try the above pro-active approach because working out exacerbates the problem. To this day though, I can only have a two scoop weight gainer shake or it will come right back up. All I can tell you is it will only get worse, you will be so sick you won’t be able to lift your dick.