I can't speak to your particular situation, but it took me nearly 8 months to get medically pre-cleared and I'm a perfectly healthy 22 yr old.
With that said, I wouldn't be concerned, the pc is incredibly prudent when it comes to the medical clearance process. My advice would be to speak to a pre-service nurse. Sometimes you need to prod them a bit to learn specifics. While the bureaucracy can be frustrating, staying engaged is the best way to expedite the process.