I'm doing a swimming challenge on Beginner Athlete as well this month with a goal of 10,000 yards. I'm at 5,700 yards so far and have almost 3 weeks left this month. I made a modest goal because at the beginning of the month I was still not feeling like I was a "swimmer," but something just happened in one of my sessions (OK, the something was my GF who is a coach, not for swimming, but still the coach mentality, who pushed me to do 150 more which pushed me past what I had ever swam in a workout before). Something just clicked and I can just swim now. I'm not sure what happened, but I found a rhythm which allowed me to just keep going and going. Now I just love swimming and have to force myself to stop so I don't injure myself!