Whats wrong with my puppy????

ok so today i gave my puppy his first shot(second out of third dose) everything was ok untill a couple minutes he startedacting differnt because he is ussaly really playfull but he was just laying down so i picked him up and he starts wimpering in pain so i put hemm down and i pet him and then he starts wimpering again so i put himm to sleep with me on the bed and he stayed with me when he ussaly leaves me in a couple of secounds so i grabed his paw again and he wipers again so i want to know whats wrong with my puppy i gave him the shot the same way i gave it to him last time and i did it how the vet tought me so was there anything wrong with the shot???? please help my puppy means the world to me i will give ten points.