Retaking AS Bio and Maths

I got 55% for AS biology and 57% for AS maths. I’m currently doing A level maths,physics and biology. I’m left with 2 more papers for each of the subjects. Should I retake AS biology and maths if my target grade is a B (meaning I’m writing AS and A level in one sitting) or should I just work hard in a level bio and physics in hopes that my grade will rise to a B for both ???? Please help