That's a pretty common issue. You've installed your WordPress files in the sub-directory /wordpress. That means when you changed the urls in your General settings without first moving the files to the root of your domain, you prevent WordPress from looking in the correct spot for all of its files. The 403 error at root is probably because your .htaccess file prevents casual browsing. That's a good thing. In a nutshell: Your site is at shad0wpact.com/wordpress and you told WordPress it should look for it at shad0wpact.com instead.
You need to fix the urls so they point back to the sub-directory in order to get back in. Here's a couple ways you can fix that. Changing The Site URL
Afterwards, if you were thinking about moving your site into the root of your domain, or of leaving the files where they are and serving it from root, here's some help on how to do that. Moving WordPress On Your Existing Server
You're going to want to look all of those directions over well, before jumping right in. There's a couple steps that can trip you up if you get them out of order.