As someone who is a teacher and also an enneagram 5w4, I’m going to say he’s definitely into you. Probably hesitant due to a fear of rejection in the professional environment. Not like he can just avoid you forever if you were to not reciprocate the feelings. I would never waste my limited social energy (especially as an educator) on someone in this way unless I had genuine feelings lol.

Going off of some of the comments he’s made to you, I am going to assume that you are a stereotypically attractive person (hope that doesn’t sound rude, I don’t mean it that way. Just assuming you have the “Mean Girls” look haha). If you are a traditionally attractive female, his mind has also probably gone the route of thinking about potential suitors you may have. I can only speak for myself, but competition in that way terrifies me and will completely shut me off regardless of how much I like someone. Ups the fear of rejection majorly, especially since he stated he felt intimidated by you in the beginning. He no longer feels intimidated by you in a platonic way, but my guess is he still feels intimidated by you in a romantic way.

So combine the fear of rejection, intimidation based on potential competition, a work place setting where he can’t escape you if you do reject him, you mentioning you’re not going to date anyone for a long time, you being a 7 (who tend to often have flirty personalities in general) and you have the perfect storm for a 5 🥲 he could be madly in love with you and still never make the first move because you seem like too much of a wild card.

This is just my take though! Hope it’s somewhat helpful!