Hi hi purplecurlz,
welcome.
You can burp a sleeping baby, try patting upwards, 1 direction.
But there are times that breast-fed BBs don't need burping,
he may be crying cause he wants to be carried.
He may just want to suck for comfort.
Maybe you can try this,
sit yourself comfortably on your bed, back against wall/bed's headrest,
back lean on pillows, arms on pillow,
make sure you are really really comfortable,
then breast-feed your BB.
When BB falls asleep, you bring his head to between your breast,
then both you & BB can sleep together.
This way, he can hear your heartbeat, feel warm & safe.