The high school student who went viral for making faces behind President Donald Trump during a rally in Montana Thursday thinks he was kicked out of the event for not being "enthusiastic" enough.

Tyler Linfesty — who became knows as “plaid shirt guy” on social media — was removed from his position behind Trump at a rally in Billings, Montana Thursday. Afterward, Secret Service looked at his ID and told him to leave, Linfesty told CNN Friday.

He said no one specifically told him why he was being kicked out, but he suspects he wasn't showing the proper amount of excitement during Trump's speech.

Linfesty, a high school senior, said the people set to stand behind the president were told: “you have to be enthusiastic, you have to be clapping, you have to be cheering for Donald Trump.”

He said he and his friends were asked to wear Make America Great Again hats, but he declined.

He was positioned right behind the president, a spot visible in most TV camera shots. Linfesty, who wears a Democratic socialist pin, reacted in real-time to what Trump was saying by raising his eyebrows and mouthing responses.

Linfesty said he disagreed with “plenty” of what the president said but wasn’t against all of it. In fact, he said he clapped when Trump “railed against” the North American Free Trade Agreement (NAFTA) and when the president said the 2016 Democratic primary was stolen from Bernie Sanders.

Linfesty said the facial expressions that caused him to go viral were just his natural reactions to what the president was saying.

“I wasn’t trying to protest, those were just my actual honest reactions,” Linfesty told CNN.

He said he wasn't there to cause a scene. He just wanted to see the president and hear his speech.

"I mean I’m not going to pass up the opportunity to see the president of the United States,” he said.

At some point, the Trump team appeared to have had enough. A woman came up and told Linfesty she was replacing him. His friends were also replaced.