As long as he ate one of the pinkies don't worry about him. If he ate one on Friday, too, then he should be pretty well fed. Since the pinkies were still cold that may be why he wasn't interested. In any case, if he is eating regularly, and simply ate a little less than usual today, there is no problem.
I think Cornsnakekeeper is right in that it is fine to give him all three pinkies together in one meal, assuming he is large enough. Unless he was a very late hatchling, he probably is.