My first symptom was weight loss, weakness & fatigue. I went from weighing 210 to 150 in 8 months time. I had no pain while eating during that time. Then, all at once it felt like a knife in my chest every time I ate, I had no sensation or feeling of having to vomit. Then I noticed the black stool. This all happened in 8 moths time. By the time there are symptoms with this type of cancer, it progresses quickly. In my case just a few months.
This cancer more common in older men. I was 58 at the time of diagnosis.
My cousin has a Hiatal hernia & has the same symptoms as you. It could be a lot of things , even uncontrolled GERD. I wouldn't jump into the cancer boat just yet!