Hello!
Personally, I wouldn’t worry too much about your grade in that one particular class. Not only is the class difficult just based on its specific curriculum but (since it is an AP), you can afford to not get an A. I’m not sure what colleges you are looking into, but I think this would apply to even top tier universities.
As for your extracurriculars, I strongly believe in ‘quality over quantity.’ While four extracurriculars may not seem like a lot, if you excel in them, I wouldn’t worry!
If you really want to improve your grade, maybe you could ask your teacher for any opportunities for extra credit? I’m not sure if your school allows this, but a quick email to your teacher would never hurt. However, if you are comfortable enough to ask them in person, that may be the better option as you would appear more committed to the class and in need of some bonus points.
Hope this helped! :)
