Anytime you have sharp pain in your chest, anywhere in your chest, call your DR or go straight to the ER because you never know if it is your heart.
So do that first.
The fact that it goes away with antacids would tell me it might be acide reflux. this causes a burning sensation in the back of your throat all the way down your esophagus.
But it is better safe then sorry-Call your DR or go to the ER.