Site issues after Plugin install

Hello! I recently installed a few plugins on my site. I then noticed my site was having some issues. The login link no longer works, the drop down menu's don't show, the header banner won't show, and some rows are extending the full width. All of this occurred after I installed a WordPress plugin called Super Socializer. I already removed the plugin, but the issues are still occurring. I'm not sure how to go about finding if it left something behind that would be causing this issue. Thanks for your help!

This is for my site SuperArtistHQ.com and I've granted access.