Help! One month old is always hungry!?

My baby will be a month tomorrow and is taking 3 1/2 oz every 1.5-2 hrs. and sometimes starts to cry a half hour after feeding. I give her an ounce more and that seems to suffice. Should I just up her feedings to 4 or 5 ounces? She always finishes her bottles and rarely spits up. And she frequently has gas. I give her mylicon but I don't think it helps. I don't want to overfeed and don't see the ped until next monday.