Shit really happens. I was really scared when I had discovered that half of the template of my blog was deleted as I was merely updating a post. I could not see any post including the archives. It took sometime to overcome the panic and fortunately I was saved by a recent backup of the current template. Thanks god nothing happened with my posts as I reinstated everything by republishing the entire site.
So if you are a new blogger user better save a copy of your template somewhere. You never know when you are going to be needing this. And if you have an Gmail account, it is better to mention that in the settings so that every post would be mailed to you. You can keep that as an archive of your posts.