With regards to dealing with being 'short', take some cues from successful 'short' men and how they act. In fact, take an actor whose height never was an issue in getting cast as a badass. Think about young Al Pacino, like how he appeared in the Godfather movies.
Well-dressed, carries himself with a quiet confidence. In the movies there's always an underlying menace, something sinister bubbling under the surface.
And Pacino shows his badassery mainly through the way he moves. Unhurried, never rushed. Even outnumbered or outgunned, he’s in control of himself. No nervousness or agitation. Clear talker, tall walker. He looks people squarely in the eye, not intimidated in the least if someone is taller.
If you stop caring about your height, but change your behaviour to that of a taller man, nobody will care about your height, just like Pacino.