Hey there, i'm an european and since few years back i'm going to american ( and japanese) conventions my first con expierence was Anime Expo and i was also solo, even though i have a pretty outgoing personality i realy feel that your among friends at a con and since you cosplay i'm pretty sure people will talk to you / ask for pictures and ofcourse i'm pretty sure any cosplay gatherings will accept you :) so no worries and just enjoy your time at fanime