How do I stop gun from shooting when uneqipped?

When I unequip my gun, it still shoots from the last place the shootPart was. Also, when spamming 1 (or whatever backpack slot its in) it shoots way faster than intended. This is my script:

local player = game.Players.LocalPlayer
local mouse = player:GetMouse()
local tool = script.Parent


local mouseDown = false
local canPlay = true
local sound = script.Parent.shoot
local mouse = game.Players.LocalPlayer:GetMouse()


mouse.Button1Down:Connect(function()
    mouseDown = true
end)

mouse.Button1Up:Connect(function()
    mouseDown = false
end)


tool.Equipped:Connect(function()

    while wait(0.2) do
        if mouseDown then
            if canPlay then
                canPlay = false

                local ray = Ray.new(tool.shootPart.CFrame.p, (mouse.Hit.p - tool.shootPart.CFrame.p).unit * 300)
                local part, position = workspace:FindPartOnRay(ray, player.Character, false, true)

                local beam = Instance.new("Part", workspace)
                beam.BrickColor = BrickColor.new("Brick yellow")
                beam.FormFactor = "Custom"
                beam.Material = "Neon"
                beam.Transparency = 0.5
                beam.Anchored = true
                beam.Locked = true
                beam.CanCollide = false

                local distance = (tool.shootPart.CFrame.p - position).magnitude
                beam.Size = Vector3.new(0.1, 0.1, distance)
                beam.CFrame = CFrame.new(tool.shootPart.CFrame.p, position) * CFrame.new(0, 0, -distance / 2)

                game:GetService("Debris"):AddItem(beam, 0.1)

                if part then
                    local humanoid = part.Parent:FindFirstChild("Humanoid")

                    if not humanoid then
                        humanoid = part.Parent.Parent:FindFirstChild("Humanoid")
                    end

                    if humanoid then
                        humanoid:TakeDamage(49)
                    end
                end

                sound:Play()

                canPlay = true
            end
        end
    end
end)

I'm a fairly new scripter so any help is appreciated.