... you do realize that adding a user account also requires Admin, right?
A better bet is to actually log in as the Admin account. This *should* be possible if you use the recovery console (on Win7 and down you could do it from Safe Mode even if the Admin account was disabled, but I think they removed that from Win8 as a security threat).
There are progressively sillier other ways I know of to fix things, such as extracting the computer's hard drive/SSD (assuming it's removable) and editing it using another computer, but there really should be a way to fix the problem. Given what you said, I'm actually kind of shocked you can still sign into your PC as is.
Out of curiosity, what on earth possessed you to delete an in-use drive? That's... um, well, it's like one of those jokes about boneheaded tech support calls. At least you backed it up first...?