Are you certain that you purchased the music through the iTunes Store account you're current signed into? There's no possibility that the music was purchased using a different account? If you're certain you're in the correct account, go to this article and confirm that redownloading of music is available in your country:
It's rare that films have been licensed for re-downloading and not music, but there are countries where it is so.
I guessed that might be the case. I think there's only one other European country where movies can be re-downloaded but not music. You can contact the iTunes Store, explain what happened, and they may grant a re-download as an exception. No guarantees, but it's worth a try. Go here:
to report the issue to the iTunes Store.