Terrible gas problems. Help!

My 2 month old has horrible gas. His dr switched him to similac alimentum 4 days ago. Yesterday was his worst day, he spent almost the entire day crying. His belly was super hard. I feel like I've tried everything! Massages, chamomile tea, bay leaf tea, mylicon drops and now gripe water. Nothing works. Anyone have any suggestions? He's in pain and not getting any rest and I'm going crazy!!