Before Saturday he had to settle for a place on the bench at a side having its worst run in over five years.
But the 21-year-old former Celtic striker has maintained a positive attitude, exemplified by non-stop running in the 3-0 win over Brentford on Saturday - the Addicks' first victory since November 8.
And he says he never had a doubt the side would turn the corner.
"I saw in training we've got two or three players for every position," he said. "You see at right back we've got Sols (Chris Solly) and Lawrie Wilson, at left-back Wiggins and Foxy. At centre-half we've got four and five and then in goal (Stephen Henderson) Hendo comes back. We've got a very good squad. A small squad but a very good one.
"I'd never thought we would get in the relegation zone as it's just been small things causing us problems."
Watt was a half-time substitute in the 3-2 defeat against Norwich last Tuesday but did grab his first goal for the club. He didn't get on the scoresheet against Brentford but capped a man of the match performance by teeing up Igor Vetokele for the second goal.
But he was just overjoyed to be on the winning team for the first time in his Charlton career.
"Nothing beats the feeling of winning," he said. "When you lose so many games you're thinking about it all the time. Now we can enjoy it.
"We controlled the game. On Tuesday we were a bit nervous in the first half. We weren't on our game but today we wanted to make sure we won and not make any mistakes after conceding the late goal on Tuesday.
"Everybody as a team just clicked."
Watt has been given the reputation of having a bad attitude after a series of run-ins with managers in his short career.
However, none of that has been seen at Charlton.
The Addicks striker praised the fans' support of him in the opening weeks at the club. And he said another key reason for his positive mood is head coach Guy Luzon.
The Israeli was in charge of Standard Liege when the Belgian side signed Watt from Celtic last year.
Watt spoke glowingly of his managerial style.
"He backed me at Standard," said Watt. "I don't think the club really wanted to sign me. He had reports I had a bad attitude as you've probably heard. He said 'look, be honest with me and if you tell me you won't cause me problems I'll sign you on the spot'. I was honest, I told him everything.
"He signed me, always pulled me in his office, worked hard with me and told me where to improve. He's given me confidence.
"He's come in here and it's been difficult for him. Bob (Peeters) signed me and Guy took me on. I've had two good managers in a month. He's not won his first couple of games but hopefully he can kick on now."
Watt's also keen to continue his partnership with Vetokele with the duo notching three goals between them in the last game and a half.
"It's easy to play with a player like that," said Watt. "He's unbelievable. You don't get bought for x amount of money if you're not good. Even in training you see his quality. He's good on the ball and he's good in the air for a little guy."