That price does seem pretty high. Although I do think that the Corolla's are worth every penny you spend on them.
If you Kelly blue book the 2008 Corolla the highest model they have should cost around $17,000.
So yea, I think you did pay a little more than you should have for that Corolla, even with the few extras your Corolla has.
But the good news is that you got an AWESOME car and I think you still make a wise decision in buying this Corolla. You will be able to keep this car for a long time and will do more than pay itself off in the long run.
http://www.kbb.com/KBB/UsedCars/Pric...0|2146151|true
Hope that helped. Good luck!