Charlie Brown forgot to bring a roll of paper, apparently.
I only mention it because there's a fansite devoted to Charles Shulz called aaugh.com, based on the way he lettered Charlie Brown's exasperations. Your "u"s are flatter on the bottom, but the other differences are really minor. It just looked weird sitting on top of your art instead of, say, over a pitcher's mound or a low brick wall.
I make that noise when I haven't eaten any roughage for a while, too...
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