Oreo- my rabbit

Question
I have had oreo for about 9 years.  He has never had any problems; until 2 days ago.  I notice there was some drainge coming form his eyes and that he didn't look the same when he was hopping around.  He looks like his back and hind legs are stiff.  He can still get around, so I don't think he broke anything, maybe sprained though?!  I also noticed that his poop wasn't normal, some pieces where where small and others where kind of clumped together.  I took him to the vet and they said it could be a couple of things.  He could have a sprain, bacterial infection, or he could just be developing arthritice but that woulnd't really answer why he has all these other symptoms happening.  Today(2 day) I notice his left ear is a little swollen.  ITs all very strange and I have no idea what to do.  I really hope you could help me solve this problem.  He's my baby.  :(

ps.
his stolls looks more normal and he is still  eating and drinking fine.
Here are the meds. the vet gave me for him..........
Metacam(once a day;0.4cc); sulfatrim suspension(twice a day;2cc); regian oral(twice a day;1cc)

Answer
It sounds like you did the right thing taking him to the vet, keep in mind that a 9yr+ rabbits is coming to the end of his life cycle. Which means just like in humans, things aren't going to be working right. And because I am not a vet nor can I physically see the rabbit, I can't offer you any concrete answers, I will however give you some suggestions on things to look up.

If your vet is unsure of what is going on, but you think that the rabbit needs more help you might try calling around to the vets in the area to find which one is best suited to handle a rabbit.

Also check out these websites for more information on rabbit illness to maybe give you a idea of what is going on in your bun or something you could take and show your vet.
http://www.islandgems.net/medical.html
http://www.welshrabbitry.com/lionheadrabbitcare.html

Good Luck!
Amy