Haters gonna hate, don't change your name if you don't want to - but also, try not to take things so hard. I'm also Arab, and my LS-mates call me a terrorist, while I call them dirty spics, crackers, Canadians, gingers, and so on (those are the nicer examples xD; ); in 99% of cases people are just being friendly in a coarse manner, and if you really dislike it, you can just send them a tell explaining the situation and asking to not be referred to in such manners.