Don't sweat it, the grade boundaries for biology are ridiculously low (at least for AQA).
Also we still have another paper so if you feel like you did bad on p1 put some more effort into revising for p2. Maybe you will end up balancing out your mistakes.
ALSO.... I would suggest editing your post because it gives details about the paper and I don't think the exam boards like that, even if pretty much everyone has finished their biology already.