Open Question: What does heartburn feel like? What could be wrong with me?

What it feels like heartburn? It all started in the past few days. I will eat a little food, my stomach felt this would blow up, then my chest feels like it is on fire now …. And I super gas. I have a stomach condition once, in my stomach produces too much acid, but also take medicine, it is gone, it is a few years ago. Do you think it might come back? Or can not be something else? I know that all this occurred in the pregnancy too … Yes, I have been in the last 9 or 10 months, not pregnant, so I very much doubt it is unsafe sex. What is not?