I studied Psychology (Got an A which helped), Biology, Eng Lit, As level history.
The thing to realise is that if you are considering a career in psychology you need to do a BPS approved psych degree, they are all BSc psych degrees, not BA psych!
My degree had lots of stats and biology as BPS accredited course cover neuroscience, cognitive psych, pain management, memory, the senses. All of which are biology based. However the course also included sociological psych to a degree.
I have to admit I got quite a shock when I realised the extent of stats in the course, but universities that want their students to do well really support you with the stats. We had stats lectures, workshops and you could get one to one help.
My degree was definitely a jump up from A level, yes in the first year they cover some things from A level psych as they are training to get everyone on the same page, as some may not have done A level psych. But your 2nd and 3rd year is definitely completely different and much harder than A-level psych.
Hope that helps.
Fitzyditzy
p.s. my cohort always collectively scored higher on the more sciencey (perceived as harder) assignments than topics in social psychology!