That's incorrect. It contains both a subject and a verb. "I do" is a complete sentence, "I do not" is a complete sentence, and so too is its shortened form "I don't." Assuredly, "I do not need three ways to say the same thing", which is what that sentence really means when you unravel the contraction and ellipsis, is likewise a complete sentence.

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Get it right!

I think Dr. Pedantic sucks dick.

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I wanted my half in the middle and I wound up on the edge.

I do not engage in the act of fellatio as the active participant.

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Get it right!

... at this time.

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"Jelly-belly gigglin, dancin and a-wigglin, honey that's the way I am!" Janice the Muppet