U already make it to JC2 u should continue.
Arts subjects like Econs, Geog, Lit, History- harder to score
unlike Sc. & Maths, u have to write tonnes of essays.
It is very common to fail but don't be discourage, the actual "A'
level isn't so bad as the prelims.
Make a point to study in sch. so u can consult your tutors
more.
Some teachers are very helpful.
Form a study group if u have problems studying alone. U & your
friends can 'test' each other. Set a timetable & make sure u
stick to it.
Very impt to study 2- 3 hrs consistently & do your 10-yrs
series. Also try & get guide books for Lit.
If u have friends in the better jcs, u can try & borrow their
notes cos I know a lot of their teachers 'feed' them.