McTominay described the FA Cup exit to Leicester before the international break as "a kick in the teeth" but added that the 3-1 defeat at the King Power Stadium is no reason to panic ahead of the final run-in which could still see United finish second in the Premier League and lift the Europa League trophy.
"We've got a good group of players with top, top quality," McTominay told ESPN.
"People are quite quick to forget how well we've done at times. It's the sloppy results that have let us down. This team is evolving. It's not a time to panic."
Draws with Austria and Israel followed by a 4-0 win over the Faroe Islands mean Scotland sit second in their World Cup qualifying group and can now turn their attention to this summer's European Championships, their first major tournament for more than 20 years.
Speaking before facing the Faroe Islands, McTominay spoke about Scotland having "the arrogance" to dominate games and it came to fruition with an impressive performance at Hampden Park.
"We have to keep improving," McTominay added. "We're a team that's getting more and more caps behind us. Hopefully we can get to a stage where we're going to the Euros in a positive frame of mind.
"I think we all share the same opinion that we can do more. All of us as a team, I think it's important for us to have that belief in ourselves.
"There's no pressure for us. We haven't qualified for a tournament for many, many years so I think the pressure is minimal. You just have to play the game and do your best. The shackles are off and it's a chance for us to make a name for ourselves."
Playing at the tournament will cap a fine season for McTominay, during which he has established himself for both club and country. It is already his most successful campaign in terms of appearances and goals but the 24-year-old said there is more to come.
"My parents raised me to be humble and hard working," he added. "I'm not perfect every game and I know that. I've got a lot to improve on but there's also things I do well so I'm just trying to improve and kick start my game to another level. I just want to do my best. It's about consistency and playing well over the course of a season."