I couldn't burp and the air got trapped inside, it was excrutiatingly painfull... be very glad you can and do burp, in fact I encourage it as often as possible. The other alternative is an NG tube and two days in the hospital. That's just my experience. Thankfully, there is medicine that will help you burp, so I'm hoping all is going to be fine now. I however, received my first fill last Thursday and was very worried that the problem would come back. No problems so far, but there is a pressure there that doesn't seem to go away. It's not painful (as of now) but it still worries me.
BURP AWAY and smile sheepishly if anyone says anything.