The Mercedes driver fell 20 points behind team-mate Kimi Antonelli - who won his third consecutive race at the Miami Grand Prix at the weekend - in the championship after only finishing fourth in Florida but insists that he hasn't "forgotten how to drive" after being left trailing in the Italian youngster's wake.
Russell told Sky Sports F1: "He [Antonelli] is a fantastic driver and has been exceptionally quick since day one. He's won all of the championships as a youngster.
"I've still got confidence in myself and have also been there. I've not forgotten how to drive. It's just a little bit of a tricky run but we are four races down, a long way to go and I think, we will reassess things over the next few weeks."
Russell admits he had a "difficult" day on the Miami track but was optimistic about the speed he found in the closing stages of the race at a circuit where he tends to struggle.
The six-time race winner said: "A difficult race. The beginning felt OK. Those early laps I was in the fight, then the hard tyre I was nowhere.
"I got some ideas in the last 10 laps. We were much more competitive. I made some quite big changes with my differentials and brake bias and was much closer to what Kimi was running this whole weekend, and it made a bigger impact than I thought.
"Not a good weekend. I know this place is a real tough one for me. The real test will come at the next few."
Russell claims that he is not thinking about the championship at present because lots can change over the course of the season.
He said of Antonelli: "Clearly, he’s in a really great place at the moment and momentum is with him but I’ve experienced myself in championships I’ve won on how momentum swings throughout the year.
"Also, looking at the championship last year, to be honest, I’m not even considering it. It’s just I want to get back onto the top step at the podium.
"The first three races, I had the performance to do that. This weekend, I did not have the performance to do that. So I could be standing here now with three very different results from the previous races, and then this just being a bit of a one-off. But obviously, things worked out differently in Japan and China."
