A 25-year-old North Shore man who lost his lower leg in a shark attack last week is on the road to recovery.

“It’s a day-by-day process, definitely,” Colin Cook said during a news conference Friday at the Queen’s Medical Center. “The first four or five days were really hard. … It’s kinda getting better slowly.”

Cook, a native of Tiverton, R.I., was discharged from Queen’s on Friday afternoon and transferred to the Rehabilitation Hospital of the Pacific in Honolulu, where he will be for about two weeks. He then plans to return to the mainland for a few months before resuming his surfboard manufacturing business.

Relatives, who flew in from the mainland soon after the attack, accompanied Cook at the news conference. Also in attendance was North Shore resident Keoni Bowthorpe, who brought Cook to shore on a stand-up paddleboard after the Oct. 9 shark attack at the North Shore surf spot known as Leftovers.

Cook said he was sitting on his surfboard at the surf break when he saw a small fish being chased by something that he could not see. Then the surfer was suddenly struck by a 13-foot tiger shark.

“I was out there waiting for a wave, and pretty much out of nowhere, you know, like, I felt like a truck ran into me,” he said. “It had some serious power.”

He added, “It happened so fast that it took a couple of seconds to realize what it was.”

The shark grabbed his left leg and dragged him underwater. Cook said he tried to fight it off, pushing the shark away with his left hand and punching it repeatedly with his right hand. He then swam to the water’s surface, spotted Bowthorpe and yelled for help.

Bowthorpe, 33, was about 150 yards away and paddling toward shore when he thought he heard something. “So I turned around and I saw a shark hit him. I saw it, you know, drag him down.”

He then paddled straight to Cook’s aid, fending the shark off with his paddle while the surfer made his way to the paddleboard and climbed onto Bowthorpe’s back.

“It was a persistent shark. It kept coming around and coming after us,” said Cook, who along with his family lauded Bowthorpe as a hero.

“He paddled there with the shark on me. He was able to get me to the beach to safety,” Cook said. “I just can’t thank him enough for what he’s done and his bravery.”

As the men reached shore, people rushed to help Cook, who was later drifting in and out of consciousness when he arrived at a hospital.

The shark had severed his left leg at the knee, but doctors performed an amputation right above the knee because of tissue damage. Cook also lost a third of the middle finger on his left hand and needed stitches on his index and pinkie fingers.

On the day of the attack, Cook’s father, Glenn, received a call in Boston about the incident from John “JC” Carper, Cook’s good friend and mentor. “I literally sank to my knees,” Cook’s father said at the news conference.

Ten minutes later the phone rang again. “It’s (Cook) in the ambulance. He borrowed the ambulance driver’s phone. He’s telling me, ‘Dad, don’t worry. I’m all right,’” said Cook’s father as his voice broke.

Friends have set up a GoFundMe online fundraising account on behalf of Cook’s family to help with medical expenses and a prosthetic leg. On Friday afternoon donations tallied $54,400, surpassing the campaign’s $50,000 goal.

Among Cook’s supporters are shark attack survivors Michael Coots and Bethany Hamilton. In 1997 Coots lost his lower right leg in a shark attack while bodyboarding at Kauai’s Majors Bay. Six weeks later he was back in the water, bodyboarding.

In 2003 Hamilton lost her left arm just below the shoulder in a shark attack while at Tunnels, a surf spot on Kauai’s North Shore. She was back in the water a month later.

Cook hopes to soon return to surfing — including to the spot where the attack occurred.

“I’ve got nothing but respect for sharks. They’re beautiful animals and creatures,” he said. The ocean is “their house, not ours.”

For information about assisting Cook with medical expenses, visit gofundme.com/surfcolin.