Never trust your webhost to do backups for you. I was an IT guy for some pretty high power institutions and sometimes backups were missed. Systems fail. You can never get back 100% of your changes when an IT outage occurs. You can only get back the changes you made before the last backup. This could be as much as a week and no less than 24 hours usually.

So do backups yourself. Let me know you circumstance I may be able to give you some of the scripts I use depending on your circumstance.