I\'m working on a project:
You're saying you're using Dropbox to restore mistakes (or "can"), so in effect, you're using Dropbox as your version control. A very simple, badly designed one. Dropbox is great for many things, but it won't help you figure out which files were changed together in the same time, or return a folder to a particular snapshot.
These are things that a "proper" version control can do better for you.