ignored

why is it that whenever i join a conversation the mood always changes? i don't get it, i'm always trying to be nice to people when they approach me, so why am i being ignored? i sound like a 5 year old without any friends LOL but anyways im kinda sad about this. maybe it's bc im hella awkward and i kinda fucked up most of my friendships by being "annoying". that still pisses me off and idk what to do about it anymore. thoughts?