It's always cute when as someone insults someone else for some flaw the insulter expresses the flaw themselves.
I once had a Russian girlfriend who, criticizing her Russian friends' English, called them 'illiteral.'
I've done it too so I'm not being particularly harsh, but one should be careful when hurling insults such as 'stupid,' lest one supply evidence that one is exactly that.
Now explain the “to, too, two” thing that you’re dinging him on, ‘cuz I don’t think he picked up on it.