Watt first injured his left ring finger during the Texans' loss in Week 1 but said during the week that it was still attached, "so that's all that matters."
After Thursday's game, he said he had to check if his finger was still attached.
"It was really great until the last three plays, and then I was literally adjusting it and feeling it as I was running around and trying to chase that guy on the last play," Watt said. "I'm honestly kind of scared to take my glove off. I honestly don't know what it looks like."
Watt missed all but three regular-season games last year after needing two surgeries on his back in 2016.
The Texans entered the game with 20 players on their injury report and lost two cornerbacks during the contest. Veteran Johnathan Joseph left in the second quarter because of a shoulder injury, and 2015 first-round pick Kevin Johnson left because of a knee injury after he was checked out by the Texans' medical team on the field.
"You lose two starters, but, you know, I thought other guys stepped up and made plays," head coach Bill O'Brien said. "It was good to see those guys step up."
"I think the guys who stepped in did a great job. We kind of shuffled some guys around," Jackson said. "We pride ourselves on having a competitive roster and having guys in the secondary and in our secondary room that can step in and play at any time."