Feeling pretty down!

Saima • 32 year old mommy to three great boys! Step son Vladi (9.19.09), Eddie (10.23.13) and newest addition Ozzie (7.31.15)!
DS is 13 days old. Been fighting weight loss and mild jaundice since birth. Was trying to EBF, but my nipples got soooo sore I cried every time he fed. So, I purchased a shield and was able to feed again- was still painful but not to the point of tears. Had a LC appointment yesterday and she says he is tongue tied and instructed me to strictly pump until they can get it corrected (he has literally ruined the tips of my nipples). So, his appointment is tomorrow, I don't know if they will fix it tomorrow or just eval. But I can not make enough milk via pumping! I have noticed a drop in supply (particularly one side) since I started using the shield and he was no longer latching directly to me. I have been pumping 20/30 minutes every 2 hours every since my appointment yesterday afternoon, I am now down to getting less than an ounce total from both sides. So frustrated but am afraid to let him latch naturally since nipples are soooo bad already.... Also had to supplement twice now since appointment yesterday with formula as I just can't make enough. Definitely feeling bummed.!
Suggestions?? I already am drinking mothers milk tea and eating oatmeal everyday....