"You think too much."
Translation:Je denkt te veel.
In this case why dont we use nadenken? Je denkt te veel na? One task before was "I think about her" translated as "ik denk over haar na".
You are right, "je denkt te veel na" would be a correct translation as well.
"I think about her" could also be translated to "ik denk aan haar", but maybe that would correspond more to "I think of her".