Tanner at 6 weeks old

I took Tanner to the Vet today at Petsmart. He weighed in at 4.1 pounds. He only received 2 shots today, the Distemper Parvo LA Vaccine and the Corona Virus Vaccine. The most disturbing news from this Check-up is that he has ROUNDWORMS! (I was wondering why his stomach looked so bloated) So the Vet gave me a dewormer med and his heartworm prevention pill to give to him tonight. His next set of shots will be in 3 weeks. Here are a couple of random shots from last night. Is it normal for him to be sleeping on his back?