This script is probably step number 5 in the 'how do I start out on this web-programming lark?' journey.
There is absolutely nothing wrong with being proud of it, regardless of the language or inevitable vulnerabilities that come from being inexperienced with web development.
It's a very small leap to go from this, to understanding separation of concerns.
Esp. after he clearly told that he would really like constructive feedback and stated, that he has no real coding experience.
Why would you play elite and kick someone lower in the ranks his way? It only shows your true colors. And imho they are not really nice in any way.