I've been having a lot of gas, burping, chest burning, and nausea for the past few days with the occasional headaches what is wrong?

Heartburn?: there are a lot of things that can cause these kind of symptoms, but they sound like they could be due to heartburn. If this is not a chronic problem, you could try to treated symptomatically it first. Initially, I would try Tums, (calcium carbonate) 1 to 2 tablets when you have the symptoms, to see if it helps. If this becomes a more chronic problem, a more systematic approach may be necessary. Good luck.