I remember having heartburn so bad once that I had to stay home from work and was hovering over the toilet, gagging. Ugh, that was awful. I had it for a few days but then it went away. Never felt anything like that before or after that one experience.
Have you been finding yourself upside-down more than recently lately? I ask that in the most literal way. If you've suddenly taken up yoga, for instance, you might notice a sudden onset of heartburn. Weird but true.
What might help is taking a 14-day course of Prilosec (over the counter). Definitely nix the OJ and spaghetti, those are killers for heartburn. Try replacing all drinks with water for a week. No alcohol. Sleep with an extra pillow under your head. All those things might help somewhat.
Best of luck and let us know how it goes!