Ball Python - constipation??

I have had a ball python for about 6 months now, and he's almost a year old. For awhile there he was peeing about 3 days after eating fairly consistently. However, he went through a shed cycle a few weeks ago, and I didn't feed him for about 2 weeks because he was in shed. He was quick to eat after he had shed, and he's now eaten twice, and still no pee or poop. His most recent meal was two smaller mice (but together were still larger than his typical meal), and he was quick to eat them both. He also seems more lethargic than usual - he usually eats and chills for two or three days, but then tends to be very active at night. Since his shed he really doesn't move around much at all.

Should I be concerned that I still haven't seen any pee? He last peed on 7/12 and has since eaten two meals, and he's almost ready for another meal. His humidity stays around 60% and his tank set up is fine.

Thanks for any suggestions!!