Dear Kate,
As I'm sure you've worked out, the world of designers is one of never being totally happy with anything!
(Which isn't a bad thing as at least we have the skills to create something that does work.)
So, I'd suggest that you stick with the logo that you're happy with (at this stage of your course/level of training etc.) and learn from the feedback that you get from your fellow students and tutors in the overall scope of your project. (When I say 'learn' I'm not patronising, just picking up what you're saying about how much you know after 7 weeks.)
We're only casual bystanders throwing in our opinions - only you have the full picture in your head.
Ask 10 people what they think will always result in 10 diffferent answers on a theme, some you may not want to hear and others that are spot on and make you think 'bugger, why didn't I think of that', but that's design for you
Go with the logo you like and can talk about comfortably and see what happens. Presentation and committment to your concept is part of what your course is about, not just creating something that is right ....does that make sense?!
(I had someone in my course who could sell any concept no matter how rubbish, because he had the gift of the gab and believed in what he'd created. He's now a VERY respected designer in the States.)
Enough rambling, hopefully you'll have made a decision and can move on to the other elements of your project

without our ten penceworth of input!