Aim120 skill issue

how does more thrust help something longer with the same fins turn the same?

im still having problems, my f16c dies to practically every aim120 fired at me even if I notch but my aim120 get countered even when I fire them at 10km or below
wtf

I watched a replay and I cant explain what my aim120 is doing, it literally flies past the dude while tracking and then dives down into the ground
he wasnt even properly notching the 2 aim120s I fired

honestly it feels like I should use them just like short range IR missiles