I got pulled over today by the police?

I overtook a learner driver and did 40 in a 30 mph, i stopped and let him do the talking, i kept my calm etc etc, he did a check everthing was ok and he le me go, im worried will a letter drop in the post later in the week or do the Police normaly state whats gonna happen, im shakin here, ny help from some who has been in this situaton I would be really Geatfull to that person or persons.