I am also not a boy, but I’ve been around the sun a few times.
It definitely sounds like he likes you, and is either shy to say it outright, or figured that the action of making out with you speaks louder than words haha. 
Either way, don’t expect him to be overly wordy when you tell him your feelings, just from what I’ve read, it seems like that’s not his style, and boys often end up expressing their feelings in more subtle ways. But it’ll clear things up for you both to admit it to each other.
As for not messing things up between you, your friendship has probably hit a point of no return tbh, rejecting him would probably mess things up too. Be sure to take things slow and not move faster than both of you are comfortable with. 