He's acted this way before...?

So, I've been dating this, on ocion, wonderful person who has been treating me like a princess in the last three weeks, but now, all of a sudden he's going back to his douche baggy ways and its starting to piss me off. Usually when we wait for the bell to rind in the halls, he's holding me and giving me kisses, and being all nice and playful. This weekend and I barely got to talk to him and didnt see him at all and when we got to school he wouldnt even look at me. He asked me why I was following him around (when he had 2 other friends following him too) and when we were hanging out in the hall, everytime I went to go stand near him he would just walk away and go talk to his other friends that were in our group. He walked down the hall some and i didnt follow him at all and then he hugged me from behind and asked why I was so pissy. Umm maybe because when I asked for a kiss he said no, he wouldnt even acknowlege me, and then he tries to blame my pissy mood on me being unsocial when I was trying to. Uggg....I dont want to lose him and he isnt trying to break up with me because he's acted this way before...but it's just that he went from being so romantic and nice to being a jerkface within a weekend....What do I do and how am I supposed to act?