two large mice to one small rat???

Ok I have a 33 inch ball python and we have been for awhile feeding him to large mice because a small rat was too big for him to get down easily. Well since he has grown we have started feeding one small rat as it is now easier for him. After he eats the rat he still stays open in his cage wandering around acting like he is looking for another mouse to eat. Is this just because he is used to being fed two or is he still hungry??? Should I also get a small mouse to fed his as well or do you think the one small rat is enough???

is it making a noticeable lump?
the rat should be the size of the widest part of his body

We recently switched one of our snakes over too small rats. For us we put our hand around the ball at the thickest point to get an idea of size and then a hand around the rats widest point. Remember the rats wides part is normally fat and squishes around a little. If we feel the rat is smaller that it is safe to feed. Yes if the rat is the run of the mill pet store feeder rat it will probably bite you but it really doesn't hurt as much as surprise!

One small rat even for an adult bp once a week is usually plenty

It's important to use gram weights when talking about prey size. For instance, my rats seem to be consistently lighter in weight than what other members'. So, what's the age and weight of your snake and what gram weight are you feeding it?