Saving your profile in Mozilla Firefox?

Recently my firefox has pulled some tricks on me. It has recently twice asked whether I want to use my original user profile but doesnt let me use that. So I have had to create a new profile and I have lost my old bookmarks in the process. What to do o' mighty techno geeks? (other than change the browser)

It did that to me too once.... no idea why and i never managed to fix it.... until one day it fixed itself and lost all my new bookmarks :/

when it does that, ctrl + alt + del and go to process and end firefox, then open up firefox and it wont ask you for the profile.