HI Beth,
Well, it's true that many moms (perhaps even most) will make enough milk simply by nursing more often. Sometimes that just doesn't happen, however.
Call your ped. or Torrance Memorial, and get a referral to a lactation consultant. there is a place in Hermosa (?) Redondo (?) that also offers BF classes and groups. Do weigh your baby often (like every week) to be sure he's gaining weight.
My kiddo got really fussy at about 3 weeks of age. We thought he was colicky until I went in for a lactation apt., and found that he was latching poorly, and wasn't gaining well, and was, quite frankly, being deprived of adequate nutrition. I supplemented him with formula and nursed as much as I was able (and pumped like a madwoman).
So: see a lactation specialist, supplement with formula so your child is well-nourished. Pump and pump and pump some more (after every feeding). I also found that eating alfalfa sprouts helped boost my supply (though I think there may be some issues with whether sprouts are OK to eat raw?). Also, taking a really warm shower (or warming a damp washcloth in the microwave -- don't burn yourself!) helped. As did really trying to relax, and focus on how much i adored my baby and smelling him (sounds goofy, I know...) I've also heard that frequent sex helps. (Ha! like there's time, energy and inclination for THAT! Worth a try though. :-) )
The long and short of it is that it doesn't have to be all or nothing, some breastmilk is better than none, and formula is better than starving. My kid is one of the healthiest, slimmest 5 year olds around, and he got tons of formula.
So do your best, but remember, there is much more to being a great mom than milk production!
best of luck to you
C.