The phrase "total nerd" refers to someone who is extremely passionate and enthusiastic about intellectual or technical subjects, often at the expense of being perceived as socially awkward or uncool. Full definition
Update 6/7/2017: The Best Baby Carriers of 2017 When I say I'm a baby carrier / baby wearing geek I am not kidding... total nerd! (mbeans.com)
But I did look at myself and say «Wow, I'm a dork, I'm a teenage girl who likes Pokemon and is a total nerd», but then I felt comforted by the love of God, and saw that God saw me as a nice young lady. (redeeminggod.com)