Good work getting your submission in for consideration. I agree with Omers and Perna that there are TOO MANY other reasons that have nothing to do with you or what you presented specifically for these types of things that you could have been passed over for. Besides no one counts if you were turned down for proposals or papers; this doesn't even go down on your applications or resumes. The fact that you are staying current, challenging your field, and continuing to move ahead is a success in an of itself. You should be proud of the work. You tried, it did not work out this time, but there will be other submissions and events, and other ways to establish yourself in your field. This is a very minor bump in the road and far from failure or a true rejection b/c it may have had nothing to do with you.