Following a below-par performance in England's opening fixture defeat of Scotland, the Leicester player disappointed again during last weekend's 19-15 victory over Italy at the Stadio Olimpico and was visibly angry at being replaced by the impressive Dickson.
And with Dickson breathing down his neck for the No. 9 jersey against Triple Crown-seeking Wales, Youngs knows he needs to improve quickly.
"I've got to stay positive, there is definitely a tussle now, there always is," said Youngs. "But I've got to work very hard and try and prove myself because I'm definitely under pressure.
"As a player you pride yourself on getting the things you think are your core skills right. Sadly my running game didn't quite click at the weekend, so when you come off it's not aimed at coaches or anyone, it's aimed at yourself.
"I've watched the game back twice and it wasn't as bad as I initially thought, it wasn't great but it wasn't too bad. Hopefully if I get another chance it might click. I'm not saying it will, but hopefully it would.
"But excuses aside, I need to get back to playing my natural game, not over-think things which I think perhaps I have been doing, putting too much pressure on myself. I need to get back to enjoying it and thrive on the pressure rather than being daunted."
Were Lancaster to change his starting XV for the first time this campaign and include Dickson, the 26-year-old is convinced he can replicate his form off the bench from the start at Twickenham.
"I made the decision to follow my dream to play rugby and it's paid off," said Dickson. "I drive my standards myself, every day in training - my ability to get around the park as quick as I can, get my forwards working hard for me and organising defence.
"I know I am very capable of doing that from the start. Ben Youngs is a great player in his own right. It's the coaches' decision who they want to pick. We've got two great nines here so I've just got to see what they say."