Germany boss Low could not travel to Saturday's qualifier after suffering a "contused artery" while exercising last month.
In his absence, Germany ran out 2-0 winners thanks to goals from Leroy Sane and Marco Reus to maintain their 100 per cent record in Group C.
Sorg, who will also be in the dugout for Tuesday's home game against Estonia, was satisfied with Germany's battling display at the Borisov Arena.
"It was a bit strange after such a long time," Sorg said to RTL. "I have not looked at my phone yet to see if anyone has sent messages.
"It was essential to win – and we did it. It was important to me to overcome difficulties and win. It was important, that the boys had to go to their limit. It was an impressive performance.
"We had to deal with a deep-lying opponent, but overall it was totally fine. We wanted to go to the opponent's goal by quickly winning the ball – and that's how we did it."
Germany midfielder Ilkay Gundogan was happy with Sorg deputising for Low.
"His speech was very good, he is extremely reliable," the Manchester City star told RTL.
"He may do it a bit differently than Jogi, but also very well. He set us up perfectly."
Gundogan was substituted by Sorg in the second half but he allayed injury fears.
"That was maybe a bit old age," he joked. "After a break of two weeks, I noticed something in the adductors, because the muscle has tightened.
"But I did not want to risk anything and got a change. That's something that you learn as you grow old."