I just finished my website and I was wondering if it's legal to just add the copyrights on the bottom of the page? I didn't use any pictures or something else from Google, everything is my own.
If you're in the US, you own the copyrights to anything you've created, automatically. You don't have to register anything in the US, although registering copyrights and trademarks only further protects you. However, whenever you take a photo, create content, or upload something you've created it's automatically copyrighted to you, the creator.
This is also true in Canada. I also think copyright works this way in the UK aswell.
So I can just write on the bottom of the page: "All Rights Reserved" ? I feel like I want to make sure I have the copyrights plus I think it looks more professional.
You have the copyright automatically. So writing anything at the bottom is a matter of style. If you do write something I would put your name or company bin addition to "all rights reserved". It lets the user know who the copyright belongs to, so they know who to contact if they want permission to use any of your work.
Copyright is easier to defend in a conflict if you can show you actively defend it. Marking your copyrighted work as copyrighted is the first step.
All the works fixed on a support are de facto copyrighted. It's as old as a 1886 international law.
However @sarahc makes a point, when in a conflict you need to show that you actively defend your copyright, and that can't be shown just by adding the mention to your site but by registering it, and only that. It comes at a cost so it depends on the projects I guess.
And the Berne convention: