If your hosting provider does auto backups, or your website admin setup backups, you should be able to roll back to a previous version of your site. This process will depend on what was backed up.

Restore Database using MyPhp:
https://codex.www.ads-software.com/Restoring_Your_Database_From_Backup

If you have jetpack installed, and backups activated:
https://jetpack.com/support/how-to-perform-a-one-click-restore/