i looked up heartburn on mayoclinic. it says you might have gotten it from "Large or fatty meals". By any chance did you eat your fellow moderator, cookie?
just kidding it says you probably got it because you're pregnant. or have a life threatening disease, maybe
edit: my high moral standards have gotten the best of me. cookie, I'm deeply sorry for making a joke about how voluminous you may or may not be. I will operate under the assumption that your BMI and body fat percentages are within a healthy range