CHICAGO (CBS) — A 17-year-old boy, who was kayaking for the first time, helped rescue a man who fell into the Chicago River on Wednesday.

Emanuel Gonzalez, who graduates from high school on Thursday, was kayaking on the river near the Clark Street bridge, when he heard people yelling about a man who had fallen in the water. He saw the victim in the water, and knew he had to act quickly.

He said his adrenaline was rushing the entire time.

“My hands were shaking. My stomach started hurting,” he said. “I felt really bad for the guy.”

But fear didn’t paralyze Gonzalez. It gave him the strength to pull the unconscious man out of the river, and hold his head above water until police divers could help get him into a boat.

LISTEN: WBBM Newsradio’s Bob Roberts reports

“I got him from the neck … with his shirt, and just pulled him up,” he said.

Police Marine Unit Sgt. Karl Hajdu said the victim appeared to be in his 30s. He was wearing a suit, a tie, nice shoes and a wedding ring and had with him a suitcase bearing a Chicago address. Hajdu said witnesses indicated that the man appeared to “roll into” the water while sitting on a railing and reading along the Chicago Riverwalk.

Police said, based on eyewitness descriptions, the man might have suffered a medical emergency.

“If the man survives, the kayaker probably saved his life by holding him up,’’ Hajdu said. “He did a fabulous job.”

Marty Woulfe, of Edison Park, recorded the rescue and posted it on YouTube, showing a Police Marine Unit diver arriving to help get the man out of the water.

Officer Brian Sheehan said, in the four minutes it took his police Marine Unit boat to reach the scene, the man had begun to turn blue.

“The kayaker said he did not see what initially happened. They came upon the scene, and the man was already in the water,” Sheehan said. “At that time they took control of him and held him at the surface until we could get there. They did a great job.”

Officer Mark Jaeger was the diver who plunged into the 60-degree water to help pull the man out of the river.

“I actually jumped in, in my swimsuit and a T-shirt, with a life jacket, while Officer Sheehan … was putting on dive gear, in case the man had gone below the surface,” Jaeger said.

“He just held him until our boat was able to get there,” Hajdu said.

It all happened in less than five minutes.

Gonzalez and his kayak-mate Stephany Lopez were just glad they stayed calm.

“I just saw him in the water, and all I thought of was trying to help him get out, and I did,” Gonzalez said.

“I was kinda scared, and he was just like ‘Stay still,’” Lopez said.

Jaeger and his fellow officers said the teen’s quick thinking likely saved the man’s life.

Police said the man was unresponsive throughout the rescue. Chicago Fire Department paramedics helped ease the man up the sheer, concrete wall of the Chicago River, then got his heart beating while transporting him to Northwestern Memorial Hospital, where he was reportedly in critical condition.

The man’s suitcase also fell into the river, and was recovered by divers.

Asked if he’ll go kayaking again after what happened, Gonzalez said, “Yeah, I liked it. I liked the experience I got out of it, and then as I saw that, I was like, ‘I guess it was meant for me to kayak, and help someone.’”