Lots of spit up

Is anyone else still dealing with a lot of spit up? My guy is still spitting up a lot and having an abnormal amount of fussiness and isn't gaining much weight. We have an allergist appointment in 10 days. Our pediatrician thinks he has reflux caused by being allergic to something in my breastmilk. I'm just so worried about him and I'm at the end of my rope dealing with his constant crying. Also, I can hardly ever give him tummy time since he's always in so much pain so we are taking behind there too. I really want to find out what's wrong with him so we can all start to feel better. I'm also worried that what's wrong with him might be something serious. 😭