Instancing 3 Bullets at once?

my gun instances 3 bullets at once, but I put the line "instance" once? this might be a glitch.

gunEvent.OnServerEvent:Connect(function(plr, mouse)
	local par = RaycastParams.new()
	par.FilterDescendantsInstances = {plr.Character}
	par.FilterType = Enum.RaycastFilterType.Blacklist

	local ori = script.Parent.Handle.Position
	local direc = (mouse - ori) * 300
	local res = workspace:Raycast(ori, direc, par)

	if res and deb == true then
		deb = false
		local res2 = res.Instance
		local mod = res2:FindFirstAncestorOfClass("Model")
		local distance = (ori - res.Position).Magnitude
		local p = Instance.new("Part") 
		p.Color = Color3.fromRGB(255, 255, 127)
		p.Massless = true
		p.Anchored = true
		p.CanCollide = false
		p.Size = Vector3.new(0.1, 0.1, distance)
		p.CFrame = CFrame.lookAt(ori, res.Position)*CFrame.new(0, 0, -distance/2)
		p.Parent = workspace

I called instance once, but it spawned 3 bullets why? the rest of the script is about damaging humanoids. I even checked the whole script by doing find all, nothing. is there a problem? it used to spawn 2 bullets, now 3. ill summarize it for you. i put Instance.new("Part") once but it did it three times. i have a debounce to stop it from repeating. whats happening? i also checked CTRL + SHIFT + F and found nothing containing Instance.new("Part") except this line.

The issue could actually be from the client. A recommendation is to have a value in the weapon to the firing rate in seconds, per bullet, so that you can make a cooldown via server.

local debounce = {}
local gunEvent = game.ReplicatedStorage.Shoot

gunEvent.OnServerEvent:Connect(function(plr, mouse)
	if not debounce[plr.UserId] then
		debounce[plr.UserId] = tick()
	end
	if debounce[plr.UserId] <= tick() then
		debounce[plr.UserId] = tick() + plr.Gun.FireRate.Value
		--fire
	end	
end)

The event will be disabled as long as the debounce is active. We're using tick() which get's the seconds that have passed since the 1st of January 1970. Adding our firerate seconds on will basically allow other users to use the event, and surpass their own cooldowns so it isn't every single user when one shoots.