I finally told my brother I'm bi....and problems with a coming out in the future

I have been bi for most of my life but I guess I didn't realize it until 8th grade but even then I kept denying it all the way up until the end of my junior year and I graduated in 2014 from highshcool. Since then I have told two of my friends and one of them thought I was joking at first. He was cool with it when he discovered I was being serious and we still hang out frequently as he is a very close friend. However tonight I finally told my brother. It was really hard for me and he kept asking what it was and jokingly he asked.....do you like men? I said yeah. He was a little shocked but is perfectly fine with it and I feel really good right now, like a weight has been lifted. Now I need to tell my parents eventually....that will be very scary although my dad has asked before a few times (and he was serious) and said it was ok if I was but I denied it.The thing that bothers me is some of my friends say that there is no way I could be gay or bi, because I guess I don't come off that way at all. I ride dirt bikes, shoot guns, paintball, played sports, I workout a lot and not flamboyant in any way (not that it's bad). I guess it just goes to show that there is no definite way to tell if someone is gay or bi.I just had to post because I feel way better now that someone in my family knows....sorry for the long text....thanks for reading!