This made me so angry when I read it. As a mother of a reflux baby, I can sympathize with what you are going through. My daughter was not properly diagnosed and treated until she was ten months old. I know how difficult it is to live with the constant screaming and spitting and watching your child in pain.
In my opinion, your daughter needs to be seen immediately. If she is not keeping down baby food at her age, that is a problem. The same thing happened with my daughter. The more we fed her, the more she spit up. She gained only four ounces between months six and nine. We never saw a GI specialist, but she did have an upper GI study done to evaluate her anatomy. Fortunately for us, she had only reflux, and a switch from Zantac to Prilosec worked wonders for us. The Zantac took away the pain but not the spitting. The Prilosec is a stronger drug that is usually offered after others have failed. Our daughter is gaining weight like crazy (now, I'm worried that she is too chubby!), and she rarely spits up or cries with pain.
Sometimes with GERD, there is trial and error before the child is properly diagnosed and treated. Obviously, your daughter's current treatment is not working, and something needs to change. I would get recommendations for other GI specialists and see if someone else can see her sooner. Maybe if you call your doctor again and reiterate the severity of the situation, he/she can get you in with a GI specialist faster than you calling on your own. If nothing else works, I would see another pediatrician who will take you seriously. If she is not keeping food down and crying all night, this is not a "wait-and-see" situation. Good luck to you--I was once in your boat and know how hard it is.