I suffer from pain in the knee every times when it's cold outside and I have to walk a lot. I used to have ostgud shlatter disease. Is it connected?

Maybe... There is a potential connection here; best to see your doctor and make sure that your osgood schlatter's disease has not recurred.
Doubtful Osgood. With that limited amount of information, it's difficult to pinpoint the cause of your pain. Osgood-schlatter disease is almost exclusively seen in preteenagers and early to mid teenagers. It rarely causes pain in older individuals. One exception can occur when fragmented bone associated with former osgood-schlatter at the top of the shin bone irritates the end of the patellar tendon. See your doc!