Answer: We all go through that at least once in our lives.
Explanation: I would talk to him and strike a conversation. If he does not respect you or acts like a child then he don't deserve you. Also, if he suffered recently from a breakup then I would give him time because he is mos likely to feel down or upset. If you catch him staring at him, you should look back at him and smile back. You should go for it, talk to him <3 :D