trubble try not to worry too much about the statistics (hard I know, my result is not as good as yours!!). In case it helps at all, remember they are just stats, based on populations of people not the individual result of you and your baby. Whether or not your baby has a genetic condition is already determined and your test results don't change that, they are purely there to assist people who are high risk in deciding whether or not to have further testing.
So if you have very long odds, you can still have a child with a condition. If shorter odds, you are still very likely to have a child without a condition. But it's already decided anyway, and for anybody who is low risk (which you are) probability says you are very likely to have a child without Downs. If my odds of winning a raffle were 1 in 450, I wouldn't be expecting to get the prize, I would know there was an outside chance, but then there would still be a chance if it was 1 in 4500!
I also think that 1 in 450 sounds worse than 10 in 4500 or 100 in 45000. So across the world, if 45,000 people have your result, 44,900 of them, statistically speaking, should be unaffected. That's a vast, vast majority!
I work a lot with stats in my job, so given the different probabilities I had over the last couple of weeks, have been considering this :)