How do I move past a self perception of yelling/screaming that differs from what most people think?

I come from a history of verbal and emotional abuse, but have been a member of a recovery program for over 10 years. While talking to a close friend last night, I had one of these "ah-hah' moments.

Looking back on my past, I understand yelling/screaming as I was often the recipient of it. However, even then I rarely responded and chose to internalize most of it. When I did respond back then, I think it would have been justly termed as yelling or screaming - because I was out of control and it could get loud. Everything was all bottled up...when you opened the bottle it exploded. But that was the past.

Today I find that people will speak to me in a normal level voice but use mean or critical words - and in my head I still hear yelling and screaming. Last night, I told a good friend that I had 'screamed' at my boss due to some frustration I have been having at the job and this all hit me. I don't really 'scream' or 'yell'...not like everyone else defines it. I am more like this patient little dove...who raises a feather or two, once in a blue moon - usually over something that is very important to me...and it lasts all of 30 seconds and is done. And even then my outer voice is only slightly raised (not like real yelling or screaming) - the voice in my head is often much louder but no one hears that besides me. So why do I think that I yelled or I screamed...when no one else would have considered that I had. And why would I tell my friend that I did?