Seriously, BM is much more harder than other language, for example, there is this correction question, which uses our most common dialect in malay , thus making us confused with what is right and wrong..

Essay doesnt matter much in SPM actually, the literature and grammar part are the important part ( they are easier to score if u grasp the technique )

my 2 cents

got a b3 in spm because i messed up the essay part

i can see from ur avatar..

also i think teacher plays a big factor also.. try finding a tuition BM teacher to teach u privately, to hell with the pride, u wan improve right?