I would suggest maybe its something you are eating? Perhaps cut everything intetresting out of your diet for a few days and see if that makes a difference. The triggers for me were:
Caffiene (a cup of tea would have her spewing for 2-3days)
Chocolate
Onions
Lots of citrus
Some veges.

Other people find high dairy diets can cause some problems.

Tummy massage is a great way to aleviate the pains. Sitting with them upright can also help a little as they dont have the burny feeling so bad.
Maybe boost up one end of the cot so its a little higher?

I know what its like - I had a devil baby when I first foudn out about her intolerances to my food eating. It wsa mothers day, she was about 3-4w old, and I ate almost a whole box of choccies, devoured plenty of tea/coffee and ate half a jar of pickled onions. Poor thing screamed for 2-3 days