Phelps, who said that he "clearly made a mistake" and that the past week has been both embarrassing and uncomfortable for him, spoke with The Baltimore Sun inside Meadowbrook Aquatic Center after finishing his daily workout. While he still has goals he wants to achieve in the sport, he said, he's going to discuss it with his family and his coach, Bob Bowman.
"This is a decision of mine that I'm not going to make today and I'm not going to make tomorrow," Phelps said. "It's going to require a lot of time and energy and a lot of thinking for myself - but also talking to Bob and talking to my family and just deciding what I want to do.
"Yeah, there are still goals that I have in the pool, 100 percent. But I'm not going to let anything stand in my way. If I decide to walk away, I'll decide to walk away on my own terms. If it's now, if it's four years, who knows. But it is something I need to think about and decide what I want to do."
Bowman said that he doesn't foresee Phelps retiring until after the 2012 London Olympics but that he understands how difficult it is for the 23-year-old to live up to the public's expectations.
Phelps, who grew up in Rodgers Forge, said he realizes that his actions seem that much more foolish considering that this is his second public slip-up, after a drunken-driving arrest in 2004. He said it "definitely wasn't easy" to tell his mother, Debbie, a principal at Windsor Mill Middle School, about the picture.
"Seeing my mom reminded me of how it was the day after I got my DUI, and I swore to myself I'd never do that again," he said. "This is just a stupid thing of mine that I did, and I have to live with it."
Phelps said he has spent the past few days with his mother and two sisters after the photo was published in Britain's News of the World over the weekend. "We've been talking a lot," he said. "I've been able to get back to my family. It's part of my life I need back."
When asked whether he regularly smoked marijuana, Phelps said he did not.
"This was stupid, and I know this won't happen again," he said. "It's obviously bad judgment, and it's something I'm not proud of at all. I will say that with the mistakes that I've made in my life, I've learned from them. Every one of them. And I've become a better person. That's what I plan to do from here. It's definitely not what I wanted, and it's clearly not what my mom wanted."
It's been an intense week for Phelps, who won eight gold medals at the Beijing Olympics. A majority of his sponsors have vowed to stick with him despite the controversy, and yesterday, swimming's governing body, FINA, praised his apology. But scrutiny of his public life has become that much more prominent.
Sheriff Leon Lott of Richland County, S.C., has told reporters that he will press charges against Phelps if he can prove the swimmer smoked marijuana in his jurisdiction, where the bong photo was allegedly taken.
Pursuit of Phelps' first public comments has been fierce. "I've been waking up to guys yelling into megaphones outside my window at 7 o'clock in the morning," he said. "I've been through just about everything you can go through. I've had paparazzi people following me from my house to my mom's house. People knocking on the door. It's crazy."
Returning to the pool and training has brought a certain calm back to his life, he said. He spent yesterday afternoon swimming laps with a kickboard, working on his butterfly, doing dry-land training with a medicine ball, and joking around with Bowman and fellow Olympian Katie Hoff.
"It makes me happy," Phelps said. "It's a part of me I've always had, and I've always been happy doing it. I like getting up in the morning and having something to do. On Monday we get back to two-a-day [practices], and I'm looking forward to that. I feel more comfortable here. This is my home."
Phelps, who started a foundation after the Olympics to help teach children how to swim, acknowledged that he feels as if he's let some people down, especially younger fans who look up to him.
"I think this is like the DUI, in that it's something I can talk more about and make sure that nobody makes the same mistakes I made," he said. "What I've gone through in the last week, no one wants to go through."
While he doesn't condone Phelps' actions, Bowman said everyone makes mistakes.
"Nobody's perfect," Bowman said. "It's not acceptable, and this is not to excuse it. He definitely, from this point forward, has to decide what he wants to do. But for Michael to go through our trials, our training camp, and then the Olympics, which is unbelievably stressful, without any downtime, that's hard. Still, it's not an excuse."
If anything, Phelps said, this has reminded him that he's subject to being watched, photographed and talked about each time he enters a room.
"There are always people you can't trust," he said. "During the whole thing, I've really been able to see who my friends are, who my family are, and who really loves and supports me. They've stood by my side, from the countless text messages, phone messages, e-mails, those are your friends. All those people who are around during the good times? Those aren't your friends."