His decision to fake up the break up was inconsiderate having not put into consideration how you would have felt about it. While he did it innocently, it was hurtful to the one being played upon.
There are instances whereby you shouldn't play with someone's feelings to find out about something.
Despite his actions, you should take him back. It shows he loves you even though in the process he hurt you.
You should let him know what he did wasn't right. It shows lack of basic manners and understanding.