Yowsers!!! That could be why he's rubbing!!! Fuzzies are too small for a BP fresh out of the egg. So they're WAY too small for your BP.
He could be cruising for food. Considering there's only a fuzzy in his belly I'd say feed as soon as tonight. Typically I'd say wait at least 5 days, but a fuzzy is probably digested completely within a day or two. So I'd say give him an appropriate meal.
How much does the snake weigh? What size mice did you buy?