I've had gas in my chest on and off for over a week. Burping doesn't seem to help it and occasionally I get heart palpitations with it. Thoughts?

Exam. You must be examined, tested and diagnosed. I would also suggest an abdominal ultrasound to rule out gallbladder disease. Get an EKG and a Holter monitor.
Could be dysrhythmia. You should inquire with your provider. A heart monitor could be helpful.