Finn's (non) weight gain

Okay, so I couldn't wait until our next doctor appointment to talk to Finn's doctor about his weight issue, so I called and left a message last night. They called me back today with not so good news. It apparently is a lot more serious than the home health nurse let on. He had been trending in the 30th percentile for weight gain (adjusted age), but now is in the 7th percentile. So we have a doctor appointment next week (instead of waiting for two weeks until his 4 month well-child appt). In the meantime, we have to increase his bottling to four bottles a day so he gets the extra calories from the fortifier we have to add to my breast milk.

I'm really actually upset. My milk already seems to be decreasing (which might explain why he isn't gaining weight...if I don't have enough for him) and if we go to 4 bottles a day, that means every other time he eats will be from a bottle. That probably means that either I let my milk stop or I have to go back to pumping every 6 hours (with a baby to care for, that doesn't seem practical). I'm sure we will figure this out, but right now, I just feel like we figure one thing out (getting him to poop regularly) and then another things comes up (two steps forward, one step back). I know parenting is like that with any child, but with Finn it is just a little more critical. I just want him to be okay and to get big. And I want to keep breast feeding him. Is that selfish? Am I wrong to be upset that I may have to stop? It is the one thing I wanted so badly when all this happened with Finn and my one thing that was "normal." I'll be fine. Like I said, I'm just a little upset right now. We'll obviously know more next week and I think I'm going to call the nutritionist at Children's and talk to her about it.