Do all the controls feel normal? Does the lock control (either inside or on via the lock cylinder or auto locks) work? Does the door handle inside and out feel normal (like the driver's door)?
You should be able to pull off the interior door handle and see if it has disconnected. I'm not sure if you can get to anything else from there.
I had an un-clipped lock control on my right rear door that I was able to fix through the interior door handle hole. The front passenger lock also sticks closed sometimes (pulling the exterior door handle all the way up and slowly letting it down un-sticks it). Just play around with it some and see if you can describe what feels wrong inside the door.
Oh, and congrats on the mileage! It must be a 4-cylinder 5-speed.
-Charlie