I'm approved, so why am I not happy?

Completely normal.  I went totally *****cakes when I got my date (both times)  I just noticed you went with Dr J...girl, great choice.  When this is all said and done you'll look back and laugh about being scarred.  The Emory experience was the absolute bomb, you'll be just fine.  Regarding the failure portion, all I can say is follow the plan, don't be hardheaded and try to test the waters.  This food aint going nowhere! 

Since both me an Hubby had surgery the quote around our house was FAILURE IS NOT AN OPTION. So go ahead remove that option from the table and move on to worrying about something that is an option.
As far as the Diprovan...girl as long as they dont put you on a leisure IV drip like it seems as though MJ had, enjoy that sleep. That was some of the BEST sleep I have ever had in my life.
But all in all being nervous is normal, but all worth it in the end.

WLS is life changing.  Surgery is serious business.  Were you not feeling the pressure you would not be normal.  At five months post op I still fear failure daily, but that fear keeps me on my program. 

Use your fear to encourage 100% compliance both pre op and post op.  It is an emotional time for you.  Go with those feelings and get it out of your system.  You will be ok.  You will be succesful.