Help with .Magnitude

Hi guys, I am making a gun swing system


As you can see, when I look to Left it works fine, but when I look to the right, it doesn’t works fine, it tilts only to the Right

This is the code;

local magnitude = (Camera.CFrame.lookVector - Last).magnitude 
Last = Camera.CFrame.lookVector

So basically, I get the magnitude to know how much I need to swing the gun, but .Magnitude always returns positive, so how can I get the same result but also with negative results (Positive for left, negative for right, or the other way around)

Disregard, solved it with

	local magnitude = Camera.CFrame.LookVector:Dot(Last)
	Last = Player.Character.HumanoidRootPart.CFrame.RightVector