To add a little more Latin pedantry, "ne" is a defensible choice for a negative imperative (you'd use it with a subjunctive verb, I believe: "ne pavescas" or "ne pavescatis"), but not the only choice; the standard I learned was noli +inf ("noli pavescere" or "nolite pavescere").
Finally, the vowel of ne is long, and so if you want to write it in greek letters you should use an eta, not an epsilon (then again, you seem to be rendering vulgar latin into modern greek rather than classical latin into classical greek; I'm not even sure how to deal with a classical letter 'v' in greek).
Finally, the vowel of ne is long, and so if you want to write it in greek letters you should use an eta, not an epsilon (then again, you seem to be rendering vulgar latin into modern greek rather than classical latin into classical greek; I'm not even sure how to deal with a classical letter 'v' in greek).