Looked at your old posts. He has had Pano... perhaps you are expecting too much. 15 minutes fetch is a lot for a 6 month old who is prone to Pano.
Plus your temperatures are high 80s to low 90s. Dogs can't sweat. It may be way too hot for him. Get him a kiddie pool if you can.
Last edited by Sunflowers; 07-11-2014 at 04:16 PM.