I'm a doctor in an A&E department and I know you're going to get loads of answers on here telling you to go straight to A&E, so I want to get in first!
First of all, this does NOT sound like typical cardiac pain. Cardiac pain is a crushing, tightness around the chest, sometimes radiating into the jaw, the neck, or either arm (most often, the left arm). It is not a sharp pain
like you have described.
Secondly, unless you have a family history of ischaemic heart disease
(ie. relatives suffering heart attacks before the age of 60), you are at a very low risk of cardiac problems given your age and general health.
You've described symptoms of stomach acid and burping, which alongside the sharp central chest pain
and pain spreading up the centre of your chest, indicates that the most likely cause of your discomfort is acid reflux
I'd advise that you take some Gaviscon
and see how things settle. If you need to use it regularly, or if it doesn't make things better, see your GP who can prescribe tablets to reduce the acid in your stomach.
Whatever anyone says, you DO NOT NEED TO GO TO HOSPITAL with this. The chances of it being a cardiac problem are virtually nil when you put together your age and health status along with your symptoms.