It depends on where you work. I'd recommend to find the shittiest job possible, and then you'll be really motivated to do *ANYTHING* else. I worked in a landfill for 2 years from 16-18 and it absolutely convinced me to go to uni.
As far as psych goes, it depends on the concentration you end up going for - I'm not overly familiar with how Scottish uni works, but I know a few people who were psych majors here who ended up in good fulfilling careers, and a few who are simply working jobs that want Bachelor's degrees, that have nothing to do with psych. But I'm in the center of the US' opiate crisis, so getting addictions counseling jobs is not a difficult task.
The best advice I can give is investigate universities you'd like to go to, and contact some of the professors there and/or any related student groups' leaders. Talk to them about the major, the other professors, and what sort of opportunities you'll have - usually they're happy to share. They may even point you to other institutions which will better fit your desires if you happen to be really interested in a certain direction.