Why are you men so confusing?

Genuinely how do guys show they’re interested? Especially shy guys? There’s this guy in my class and we’ve talked before. Today he randomly came up to me and introduced himself(yes we already talked and got each others names), and starting talking to me. The class was discussing contraceptives and sex so it was already awkward.

He seems shy so it could just be nervousness? He started asking me what other contraceptives there are besides condoms… there’s no way he didn’t know… anyways, he the proceeds to walk away to the board, not write anything, and walk back near me. Then he start talking more and randomly turned around and opened a cabinet behind him and looked through an empty box? I’m so confused. Help. Am I just overthinking him being shy and awkward?