I had the same problem at one point actually…in my first year @ university, my roomates thought I was a snob…they said they used to gimme the finger behind my back cos I would just smile or nod my head at them when I walked in and would go straight to my room…lol…funny stuff! We laugh about it now…eventually once we got to know each other..we all became pretty close…and they understood thats just how I am…not a snob just kinda reserved till I get to know people !
You’re bound to run into the same thing but its part of the game I guess!