A couple of months is a BRIEF amount of time to come to a diagnosis. Even when it is clear-cut, it can take more than a couple of months. 6 months, a year, even a FEW years is common. As you're finding out, all those tests take time -- time to set up, to get down, to get evaluated, to get test results sent here and there..
They won't help with symptoms until they know the cause, most of the time. Some drugs are specific to particular diseases and harmful to others, so you don't want to be taking something that will end up causing even MORE harm.
I know the waiting is hard, but sometimes that is indeed all you can do.
...I am not a doctor, nor health professional, and don't pretend to be one, here.....