BFing and Supplementing

[ZoeyMakesThree]

DS is 4 months and not gaining well.Today pedi said I need to start supplementing after bfing him. I have been working to up my supply but that does not seem to be the issue. The pedi and LC say he looks tongue tied and I dont want to clip it at this age. Soooo, I just dont see how I will be able to have time to bf and then bottle feed after every feeding from now on. I dont want to stop bfing completely so what do I do? Is it possible to just bf at night and a couple daytime feedings and the rest be formula. I am so confused as to what to do.