I just got a 4 month old Bosten Terrier and he is eating and drinking well, but he can not poop. He tries really hard and only a little comes out and he will keep trying for about 5 minutes and then gives up. What does come out is not hard. What should I do?
Optional Information:
Age: <1; Male; Breed: boston terrier
Already Tried:
don't know what to try