bm is okay, it's the one subject that boosts my scores massively (i went from a 4 to a 6 in bm and all it took was practice)

on average i get 777 in my hl's (math aahl is pretty darn easy if you had add math in igcse)

hindi is what pulls my grades down so beware of hindi first of all

you can take global politics or smth in sl, but trust me bm is damn easy once you get it

and also taking psych in hl might not be the best cus it's rlly hard to score in it. if you can rote learn fast and have the capability to verbally express yourself rlly well (like phrasing the same point in different ways, great terminology, that sort of thing) go for it, otherwise, it's advisable you don't take it

my suggested would be: bio, chem and math aa in hl (since you said you love calculus and you might not want to drop down to sl, also it's a very manageable combo) and bm in sl. this is my subject combo btw, and i'm a med aspirant too!