No it's not bad to not have IRL friends. I have people who may call themselves my friends but they don't bother to invite me to social events (even though I probably would go). I got invited to the cinema last year which I went and enjoyed, there was 3 of us (and that's literally the only event in at least the past 5 years). In the UK it's typical to go out drinking/clubbing at 18+ as that's the legal age, though many go at 16 anyways. I wouldn't just invite myself as i'm not [insert terms here]. Currently 21.