Is it really weird to do this, or am I not alone?

I live with my dad and (in and out) my brother, I am 17 he is 20, my dad is 40, my brother sometimes has friends over (they do little projects in collgese, sometimes film for teacehes and stuff) when only they are hee, I walk around naked sometime like its nothing, i think my brother finds it weird, but nobody ever told me sanything, so i do not knowI dont like go everywhere i just get hot and take off my clothes, dont shut my door, walk ou tto the bathroom or kitchen toget water, sometimes I go into the living room to ask something, and they wont look at me, so i figure they find me wier dbut fel bad. The only time it was bad was when i walked in the middle of a film and my brothers friends looked at me for a little and looked away, when i left i heard my brother cuss at them and call them pedophiles...(Not that young anyways) So it is like a habit..is it really natural or is it a problem that they just delal with?