Stinging Pain Behind Knee After Stretching? Causes & Recovery

Question
About a year ago I'd had an ankle injury so I couldn't stretch or do any exercises, etc. Well, once my ankle got better, I got so excited I just started stretching the way I used to before the injury right away (I was really flexible, like I would be doing the splits in both directions). But after that I got this stinging feeling and stiffness behind my knee for a few weeks. I couldn't stretch at all and had to wait about a month after to start stretching again. That time I took it slow but still, the stinging and stiffness came back. Even now, I try to stretch but almost every time, the stinging and stiffness comes back. I try to do just light stretching, but when I'm stretching I don't feel any pain in my leg so I can't tell how far I can go. But the next day it hurts to the point where I can't even put a lot of weight on it and I can't straighten my leg, but there's no swelling. I only stretch about once a week because I have to wait until the stinging and stiffness go away. Does this sound like it could be a major problem, or can it be fixed? What could possibly be the problem? Thanks

Answer
it sounds like you lost some flexibility from the injury/inactivity then tried to get it back too quickly.... rest to the point of no pain then really easy stretching.... no bouncing and take 6 weeks to get back to where you were..... after inactivity the connective tissue doesn't bounce back to normal in a day or two.... it takes some work........ I think it is fixable but with nice controlled stretching and activity.