How To Cure Knee Pain After The Surgery?

I got surgery on my knee about 7 months ago. I had a plica band removed and a lateral release on the same knee. it started to feel better, so i would increase my activity just a little. Now club soccer is coming up so i started to to flutter kicks to help streghthen my knee. Since then my knee has started to hurt all over again. I am sometimes limping just when walking and i can't even really jog anymore. the doctor also never told me to go to physical therapy and it is really expensive. All i want to be able to do is walk and run again. I haven't been able to for run normal for almost a year now.