Welcome to the board. Sounds like something last minute that you needed to take care of his dog. Did he leave a telephone number or contact information for her vet? If not maybe someone on here that lives closer to you knows of a reputable vet to call. If she looks scared she probably is scared... remember yourself having your son? (that is if he is your biological child... which is not of importance here)
I have never had a pregnant dog, but I unfortunatly have a relative who is a BYB. I was at their home when their dog was ready to give birth and they just made sure she had a nice quiet private area in the house (an area in the living room). Sorry I forget what else they had around to help her. Now I wouldn't exactly say a BYB is doing things right... but the litter was ok.
I agree with the others about spaying the dog. I would have an honest conversation with him about getting her spayed. Although that may already be the plan right!?