Um, sorry but if he has had little interaction and is not even gelded yet, he probably was trying to strike at you. If he were handled more and really wanted to come up to you in a non-timid way, then I would agree that he might be trying to play or be bored. Just because it may not appear threatening, does not mean that he was not trying to strike. I am sure you are well aware already, but I would be extremely careful when stepping into a stall with him. Good luck though!