After 14.Ne4, White is threatening 15.Nxc5. Black should play 14...Qb6, then 15...h6 to prevent the knights from penetrating.
14...f5? should lose to 15.Nxc5 (threatening 16.Nxe6), then 16.Nxb7 and 17.Ng5. But Black played 15.exf6, still with the threat of 16.Nxc5.
Better than 16.Nxf6 is 16.Nxc5, threatening 17.Nxe6. If 17...Qd6, then 18.Ne4 and 19.Nxf6+.
17.f5?! isn't as good as 17.Qe1 and 18.Ng5 (or 18.g5), putting pressure on the backward pawn at e6.
Instead of 19.gxf5, I might I played 19.Bf4 or 19.Bh6 and 20.Ng5.
20...Rxg5+? is no good. Black loses the exchange. Best is 20...Rf8, and if 21.Bh6, then 21...Rf6 and Black should be OK (22.Bg5 Rf8 23.Bh6 Rf6 draws).
21...Nd5?? loses almost immediately. Black now loses his queen or gets checkmated. But White does not find the best combination. Black should play 21...Nf5, threatening 22...Qxg5+. If 22.Qd2, then 22...Nce7.
22.Qg4? White misses 22.Be6+! Kh8 (22...Kg7 leads to mate after 23.Rf7+ Kh6 24.Rxh7+ Kxg5 25.Qg4+ Kf6 26.Rf7+ Ke5 27.Qe4+ Kd6 28.Qxd5 mate) 23.Nf7+ winning the queen.
22...Ne3?? is no good. Black should try 22...Bc8 and if 23.Qh4 h5 should hold. If 23.Ne6, then 23...Qd6 should hold.
After 23.Qh4, White threatens 24.Qxh7 mate. After 23...h5 24.Be6+ Kg7 25.Rf7+ Kg8 26.Re7+ Kh8 27.Rh7 mate.
Thoughts on my recent game? It's a Closed Sicilian - my favorite opening in the world... if my opponent doesn't play it right :D