Welcome!

I feel your pain. I don't pass either; I get 'madamed' almost every day. And like you, I'm extremely uncomfortable with being thought of as a butch dyke (particularly since I don't even like women in that way!).
But you know what? I have to be myself anyway, despite what other people may say or do.
Part of the FtM transition process involves discarding female socialisation and trying to figure out how to live life as a male instead. I daresay you have been socialised to put others' needs before your own: most female-born people are socialised like that. So we can and do feel a great deal of anxiety when we decide to transition and start trying to figure out how to be male. We have been taught to never rock the boat; to never put our heads above the parapet; to seek the consensus of others before doing anything. Figuring out how to put yourself first, disregarding the opinions of others, is a
very steep learning curve when you've been socialised to do the exact opposite.
We've spent so long suppressing our natures so that we can play the part of being female that we're almost frightened to assert ourselves. It takes time, practice and a lot of patience... but I can assure you it
is worth the fight. Becoming a man involves (amongst many other things) becoming your own person and asserting your influence on your life, rather than waiting for everyone else's permission to let you do what you need to do. You already have the skills you need to learn how to become a man: you used them to learn how to play the part of a female.
So just do it.
The late, great Eleanor Roosevelt once said: "No one can make you feel inferior without your consent". Part of becoming who you really are involves withdrawing that consent. Who cares if someone wants to think you're a butch dyke? Who the heck are they to tell you who you are allowed to be? Oh, and if catcalls bother you, there's always the iPod to drown out the noise and dark glasses to prevent eye contact.

You know your own truth.
Live it.