In terms of the Ehehehe and Ehehehe teest test pages, you proceeded to move those pages across nearly all of this wiki's namespaces, with the exceptions of the File:, MediaWiki:, and Topic: namespaces (likely accounting for a combination of technical or user rights group permissions limitations). Ordinarily, this would not be a problem as you did delete the final destination page, Gadget definition talk:Ehehehe teest; however, because you did not check the box to suppress the redirect left behind from your cross-namespace page move (on wheels), a trailing redirect was left behind (which also created broken redirects and double redirects). I tried to blank the trailing redirect pages, in order to utilize Special:Nuke; however, this didn't work. So, I had to manually delete all of those trailing redirects. So, if you are going to move a page across more than one namespace, please be sure to suppress the trailing redirect, especially when it's a test page that will be deleted in relatively short order. As a matter of personal curiousity, and noting the Ehehehe and Ehehehe teest test page names, I'm curious what you were testing that necessitated moving these pages through nearly every namespace on this wiki?
In terms of Category:BangBangBangaBang, I was a bit puzzled as to why it was undeleted. Seeing no need for this obvious test category that serves no useful purpose in our page categorization system, I have redeleted it, and creation protected (or salted) it for three months at bureaucrat level. It will not be recreated for you, unless you can briefly explain to me (in approximately 1-2 sentences) why you would like it to exist.
Because the time involved in the cleanup, I have had to notify a consul of this cleanup. So, please be mindful of all tests you perform; ask questions at the community portal or on the user talk page of any bureaucrat or consul; think twice about all tests you perform, considering the effects of such test(s); and, as always, revert any tests you perform.