Puppy problem?

my 4 and a half month old neapolitan mastiff is recover from eye surgery.... it been 5 five dayy today at night i took him for he walk ... put him in his cage i let him out again he went nut running all over the place ... he was so hyper.... it not like him to be that hyper... is it because he ate something because he always has something in his mouth... he wont stop beening hyper... he wont stop moving around and figitiving in his cage ... i dont know what to dooo please help... i took him for long walks