The 28-year-old striker has scored 10 goals in 30 games for the Cottagers since joining from Everton last summer.
Having suffered with injuries for the early part of the season, Johnson had to wait until September before making his debut against Bolton.
Admitting his frustration at those setbacks, the former Toffees front man is now hoping he can contribute towards Fulham's European targets by scoring as many goals as possible.
Frustrating"Initially, it was a little frustrating," admitted Johnson. "I just wanted to be out there playing alongside my new team-mates and be a part of the squad.
"It was difficult because I wanted to show the fans what I was all about."
Johnson scored his first and second goal for Fulham against Wigan back in October, with his first goal also his 100th of his club career.
"The Wigan game was a great night for me and one that I won't forget in a hurry," he added.
"To score my 100th league goal as well as my first for the club was an amazing feeling and one that is hard to explain.
"We went on a great run after that, despite slipping up at Everton, and we really showed what a strong team we are at the Cottage.
"It's a pity we haven't replicated that form away from home because I think we could have been in or around the top."
NuisanceHe added: "I do think there is more to my game than just goals. You need your strikers to bring more to the team.
"Of course, goals are important, but equally so is working hard and making a nuisance of yourself.
"Over my career I think I've averaged something like a goal in every two and a half games.
"This season the goals probably haven't some as freely as I would have hoped, but I'm happy with my total so far and with nine games to go I'd like to add another four or five."