Help me deal with the shame please? Lolz?

Well in the past, i was almost gonna get in a fight with this ***** but I looked pretty nerdy. I punched her from like 10 feet away (im exaggerating) and then flinched because I saw a teacher. I looked like such a pansy X_X But then again in our second fight she ******* ran away. Well, anyway, the question is, how do I deal with the shame and stop hating myself for being so nerdy?