are his gums pink? How old is he? How much does he weigh?
Layla has days where she is play play play during the day and just out of it at night- and then opposite- I used to worry but now i've realized she has different moods and energy levels just like I do.
If he is eating/pooping/playing normal during the day- and his gums are pink- sounds like he is just tired after a long fun day
Layla also differs as the season do (nuts.. i know) she is CRAZY during the winter- playing her fool head off- in the summer- she slows down as the heat starts to affect her.