Can you get up a better video if you have a chance? Seems to me he is stiff in the back - something does seem off. I don't know if it is the hips or not. Could just be some sore and stiff muscles from playing too hard. I would watch him for a few days and see if it gets better, and if not, have him checked out.
BH, OB1, TR1, AD
Rottweiler/Hairy Dog mix?? Shelter rescue
Gryffon Vom Wildhaus