I am sorry you are feeling overwhelmed. DS turned 2 in Sept., and the pediatrician recommended that we have him tested because he wasn't saying sentences yet. I ended up canceling the entire process because it was just too overwhelming. Honestly, I don't believe in the entire labeling/milestone thing, and DS is doing just fine now, two months later. Each child grows and develops differently, and when they are this young, it's so difficult to determine if there is something wrong, because they are just learning everything at once!
I hope it gets better for you and you get what you want out of the process.