Swapping Tools Script?

So I wanted to ability to swap tools when pressing "q", I get no errors (I've never done this before). Am I approaching this the correct way, or am I doing something wrong?

Please note that this is not the whole script

repeat wait()
	Player = game.Players.LocalPlayer
until Player

repeat wait()
leaderstats = Player:FindFirstChild("leaderstats")
until leaderstats

local Mouse = Player:GetMouse()

local Prim = true
local Ak47 = Player.Backpack:FindFirstChild("AK47")
local M9 = Player.Backpack:FindFirstChild("M9")

function SwapW(Ep, De)
	if (Ep) and (De) then
	De.Parent = Player.Backpack
	Player.Character.Humanoid:EquipTool(Ep)
	end
end

leaderstats.InHeist.Changed:connect(function()
	if leaderstats.InHeist.Value == true then
		SwapW(Ak47, M9)
	end
end)

Mouse.KeyDown:connect(function(key)
	if key == "q" then
		if leaderstats.InHeist.Value == true then
		if Prim then
			Prim = false
			SwapW(M9, Ak47)
		elseif not Prim then
			Prim = true
			SwapW(Ak47, M9)
		end
		end
	end
end)