Are you talking about the fourth semester/sophomore comps/upper division juries, or just a regular semester jury?

Either way, the panel should have written specifically what you did well and what you need to improve. You should be able to get copies from your lessons teacher or they can at least tell you where to go for them (all music schools are different).

I failed my first fourth semester jury (or whatever your school calls it) and I had to take it again the next semester. I also had to switch professors for my lessons and I just barely passed (by one vote) the second time I took it. Then I had to change my embouchure the next semester and basically had to relearn how to play my instrument from scratch and couldn't play at a college level for months. But despite that, I still graduated with a BM in performance and a BA in music with departmental honors and am currently in the process of applying for my D.M.A. in music (not in performance though, mind you, but I still play). My point is, just because you didn't pass a jury, doesn't mean you can't ultimately succeed.

Also, it doesn't matter how MUCH you practice, it's how EFFECTIVELY you practice. It just bugs me when people say 'you need to practice X hours everyday' or 'oh, I practice X hours everyday!' Practice how much YOU need to, not how much someone else says you need to. And you don't need to announce to the world how much you've practiced. Your abilities will eventually show that. I'm getting off the soapbox now…

P.S. If anybody wants some tips for more effective practicing, PM me.