Try switching formula...
I have a 6 month old that was having problems like that when she was born ( I was also breastfeeding and giving formula). It appears that she was lactose intolerant. My doctor switched her to Similac Sensitive. It's lactose free, but milk based instead of soy. It really helped!! No more gas, spitting up or tummy aches anymore.
It's the one with the orange lid and you may not be able to find it in all grocery stores, but Wal-Mart has it. It may be worth giving it a try.