Did you use the backup tool to save a copy of the info in the database beforehand? If not, then no there’s probably no way for you to recover it (although if it were really urgent you might be able to get a backup from your host). I once overwrote a custom eCommerce checkout snippet the night before launch, and the resulting stressful night of pulling out my hair and recreating the whole thing from scratch has taught me to use the backup tool compulsively.
