Failed first PST, have to lose weight

I fail my first PST, but it wasnt on my swimming. I couldnt run. I blew out all my energy on the swim, did much better than I thought I would (as in I actually passed it) but I wasnt told my time.
I did okay on my PT part, but not nearly as good as the guys who have been on the boat crew a while. Some of them have been on for 11 months, and they were doing 100+ pushups and situps and 20+ pullups. Dont mind saying I was outclassed, its the truth.

But I was passing. When we started the run I felt fine, I was nervous but felt I had it. First two laps were 1:30 pace, but then fatigue swept in almost immediately after them. Started breathing way, way too hard, embarassingly hard. Cramps set in and, fail.

Was I ashamed? Sure. I was overconfident one second and pathetic the next. But fact is I had expected to fail on my swim to start with, I had been dreading that all the way up until I got in the pool. Then my familiar calm from karate settled in, its the same feeling before a sparring match. You are nervous to the point of dread, but then once you're up and bowing to your opponent it all goes away. I hadnt expected that ace in the hole, but I was well aware of it when it occured.

Dock Hooks is my motivator and he is a very cool guy. I kept my manners in check and my talking to a minimum around him, but he is a very open and casual man. He told me after my failed run that I should try and lose about 15 pounds, which isnt surprising considering most of the guys who had been there a while were completely cut up.

Knee pain
I ran, starting on Wednesday, with the firm intention of running every day between now and the next test. After three days pain in my left knee became apparent, and Sunday when I set out to run I took ten steps before realizing that was a bad idea. I took Sunday for rest, and when the same feeling stayed on Monday I went instead went to the stationary bike, and again today. Cross training is going to be the key here.