It really is hard to say. The worst-case-scenario is PBFD and if that is the cause, catching it early can prolong life-expectancy in some cases.
It is highly contagious and can be spread via feather dust, dander, fecal matter, oral secretions etc. Until you know what is going on with yours, don't handle other birds etc (just in case your bird does have it, you don't want to accidentally spread it to others via your clothing etc).
Again, I am sure there are other possible causes as well. I wish I could give you more information, but I think you may have to make the 3 hour drive to the vet.
If I were you, I would confirm that they could perform a PBFD test before you make the trip.
I am not trying to alarm you-- it is just one possibility--Heck, it could be mite-related, fungal, a deficiency of sorts or something else. Either way, the vet is going to be able to tell you way more than I can.