Knee pain getting worse!?

Went running yesterday (was an easy run, no issues, made sure to stretch good after warmup and cooldown) 5 minutes after my stretching my knees started getting really tight. I took Motrin and tried heat and ice but I couldn't get te tightness to go away. This morning when I woke up they both are still tight and I can't bend them (can't go completely straight and if I push my leg in I can get it to 90 degrees before it doesn't go anymore. Walking is a big issue right now (get EXTREMELY sharp pains in my knees when I walk and forget about stairs). I also am getting tingling and pins and needles behind my knee. It gets worse as the day goes on. Throughout the day I try to keep bending my knees to try as loosen them up (and avoid stiff knee) but t isn't helping! Any ideas on what it is and what it could be? It is in both my knees. What should I do from the pain other then Motrin and ice/heat???? Help!!