MacBook Air Username change

I recently tried changing my username on my laptop. I followed all the steps. when lappy restarted, my username had changed but password was still the same. the short name on the login page appears as admin, and in the system preferences/usersandgroups it appears as Administrator. my home name is written as Mac...

can someone please help me recover my username. right now ì can't delete or install things on it because of the darn username that I cannot seem to figure out..