If you are still making some milk, I suggest you talk to a lactation consultant ASAP to see if you can rescue your milk supply. I don't know how quickly supply can bounce back, but you should talk to someone knowledgeable to find out.
When you are at work tomorrow, pump and see if you can get enough for a feeding when you get home in case he refuses during the day. He might take that from a bottle even though he won't take formula.
ETA: I know you are panicked because he's not eating right now, but please try to see the long view here. Your milk supply is based on demand. The more often you nurse, the more milk your body will make. So if you keep putting him to your breast whenever you can (and pump when you are at work), even though today and tomorrow, he will be fussy because it's not enough, in a few days your supply will catch up. And let's face it, if he's not taking the bottle, he's fussy anyway, so you've got nothing to lose by going back to the breast. I know you are working today, so pump today, and tomorrow spend as much time as you can on your most comfortable chair or couch with him at your breast and water in your hand to get your supply back up.
I'm not a "nurse at all costs" mom. I know many babies are perfectly happy and healthy on formula. But from your post, it appears that your baby is not one of these, and since you are still producing some milk, it seems worth it to try to go back to nursing. A LC can really help you with this. If you were in Pittsburgh, I'd know just who to send you to, but since you are in LA, I suggest you call your local Le Leche League and ask them for a recommendation. The LLL moms usually know the best lactation consultants.