I knew I wanted to be a PT since high school. But in college I actually needed Physical Therapy for knee pain. Every time I ran, the back of my knees would hurt during the run and afterward. I actually had to stop running because the knee pain made it hard for me to climb stairs. I lived on campus at King College (a small school in Bristol, TN), where I had to walk and climb stairs a lot.
So I saw a PT here in Columbia on one of my breaks from school. He showed me several exercises, and as I did them for the next weeks-months, my pain progressively decreased. However, I was afraid of the pain returning, so I stopped running completely. At the gym I did the elliptical machine instead, which did not bother my knees.
I went through the rest of college and grad school without returning to running. I did other forms of cardio but stayed off the treadmill. Several years later, I finally decided to try jogging again. Everything I learned in PT school kept me from having knee pain. I learned how to warm up, do the right stretches and avoid hurting my knees again. So now I can jog regularly without pain! I actually do the treadmill now much more than the elliptical.
All this is to say that PT works! If you have an injury or frequently painful area, find a good PT near you! But ideally, you can learn how to think like a PT now to prevent future pain.