Enzo Fernandez had Chelsea ahead early before Marco Asensio's brace for Villa saw the hosts to victory on Saturday night.
Tielemans said, "You could see in the end the atmosphere was amazing. Us coming back into the game made it more special. We fought really well until the end and it was really important to get that win.
"We had a bit of a slow start. But we grew into the game. We had a few chances in the second half. We didn't threaten enough in the first, but were much, much better in the second. We nullified their threat. They had a few chances but we were there to win the balls and win the game."
On January arrivals Asensio and Marcus Rashford, he added: "You could tell tonight that they have a lot of quality. They are very hungry and they want to help the team. That is what we want from them."