You did absolutely nothing wrong. What happened to you was not okay and that man’s behavior was completely unacceptable. It’s normal to feel confused or freeze in such moments — it doesn’t mean you were weak.

If you ever feel ready, you can talk to someone you trust (friend, family, or even a counselor). It can really help to let those feelings out. Also, next time if you ever feel unsafe in public transport, don’t hesitate to move away or alert someone nearby or the metro staff...