Hi mloga94, can you paste the code you put in your functions.php? You could also paste your current functions.php content on pastebin.com and link to it here.
If you have made no other changes to the functions.php, it might be easiest to upload the original functions.php from the theme download. That should get the wp-admin area running again and then we can figure out the other problems.
If you have made no other changes to any of the theme files, you could also follow linkfr's advice from the other thread - delete the theme folder through your host's file manager and re-install the theme. Most of your theme settings should be restored, but check the Menus and Widgets because Menus get reset and Widgets are stored in the Inactive Widgets section of the Widgets page.