This is embarrassing; I used the usermod command to add myself to the disk group. However I forgot to use the append option! so I'm not a member of any of the groups that I was originally, now terminal says that I'm not even a sudoer (How rude!). So the question is: What are the original groups that a normal Administrator type of user is in? BTW, I am using Linux Mint Debian Edition (LMDE).
Any help is appreciated.