T.B.
First, I think it's wonderful that you are breast feeding! I am too, and I know what a wonderful bond this is for you and your baby. My baby is 8 months old and also taking solids, and breast feeding, and supplemented with formula as needed because my baby had suck issues from birth and because of her slow weight gain, it was necessary to supplement.
So, how do you know that you are not producing enough milk? Your baby is taking in 24 oz a day. Wow, I say wow because I prepare 8 oz a day and some of that is used to make my baby's cereal in the morning, she breastfeeds throughout the day (about every 2-3 hours), and she eats dinner in the evening and while my baby is still gaining weight slowly, she is gaining. I'm curious how much your baby lost. How often do you weigh your baby? I have a baby scale and I was weighing my baby daily until my lactation consultant told me to weigh her weekly because I was truly driving myself nuts with the daily fluctuations of her weight.
If your are concerned about your milk supply, I would suggest you find yourself a double electric (hospital grade is best) breast pump. A manual pump is very time consuming and you will grow tired of pumping one breast at a time. Also, you must not use what you pump out as a gauge for what you are producing. A baby nursing at the breast the the best pump, as a mechanical device cannot effectively pump a breast the way a baby can while breast feeding. Since you are a SAHM, not sure of the time constraints you deal with daily, but if you can manage it, pump after each nursing session and then pump at night just before you go to bed. I'm taking Goat's Rue, an herbal supplement for lactation.
I might also suggest you find a certified lactation consultant to assist. Is your pediatrician an advocate for formula?? To me, it sounds like he (or she) is pushing you to use formula. The more formula you give, the less your baby will take from you. I would also supplement AFTER you breastfeed. Nurse your baby on BOTH breasts and switch nurse. Do you know what switch nursing is? Nurse baby on both sides three times. When baby seems lazy, sleepy, or stops sucking, switch sides and after baby has nursed on each side 3 times, then offer a supplement. Can you increase your supply? Yes! With a manual pump? It's gonna be a challenge so think about an electric pump instead, one that pumps both sides simultaneously. Eat oatmeal, take herbal supplements (Goat's Rue, Fenugreek, or Blessed Thistle), drink liquids, and get enough rest. And nurse the baby as often as possible, even have a nursing holiday if you can manage just laying in bed for a weekend and do nothing but nurse. I know, hard to do if you have other children, or even with an older baby. Good luck!