Renee, it sounds to me like you know exactly what you're doing!
A few extra feeds and that'll probably do the trick. At any rate, your baby is most definitely not starving!

BTW, if you compare the charts in the standard baby books they hand out with teh WHO charts, you'll see that fully breastfed babies tend to put on more weight than ff ones in teh first few months. However the curves seem to level out more later on and they're often lighter at 6-12 months (this is based on my rough comparison).