Where did black go wrong?
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6...Qd6 is bad for a whole host of reasons. You need to develop Kingside pieces first and not plan to castle on Q-side
7...Ne4 does not develop efficiently. 7...e6 or g6 were better
22. Qf5...Queen is too offensive here. Plus, she doesn't make any real threats = f2 is guarded by Rf1 and Kg1, e6 guarded by d5, and d5 is guarded by Bc4. Queen never makes another move and is unable to help defend the O-O-O castle. Queen's position at f5 would have made more sense on a O-O castle.