Translation of "Nerd" in Spanish

Tom is a real nerd.

Tomás es un verdadero nerd.

And take it from me, a 17th-level nerd,

Y te lo digo yo, un nerd de nivel 17,

Or because I'm a nerd, or I have a low level of self-control,

o porque soy un nerd, o porque tengo poco autocontrol,

Four or five pens in one's shirt pocket is a dead giveaway for a nerd.

4 ó 5 bolígrafos en el bolsillo de la camisa es una clara señal de ser un gilipollas.