My elbows have been aching a bit too much recently and something weird is that it gets stuck, in my joints my tendons or something my lower and upper arm feel completely stuck together that I have to pop it open again which is really painful when I pop it open to be able to move it again. Is this bone problem, tendon or something? It has happened for some months now and sometimes happens in my knees too (bones feeling stuck together) what is this and what should I do? Moreover, my body joints have been aching too recently like everyday a new joint so I don't know if this is something affecting all joints or just severely my elbow and knee.