All I could think as I was reading this was...BREATHE, BREATHE. ; )
I don't think you're having a Bridezilla moment or a crazy moment. I just don't understand why they would charge you again if you need additional alterations. Yeah, yeah, maybe the are considered "emergency" alterations, but still, you paid for them already. To me, alterations shouldn't be considered final, until the day that you pick up your dress & walk out of the store!!!
Anyway, you should definitely try it on tonight. No need to have any regrets 7yrs later!!!