Im32 yo n having pain in both knees have hypothyroidism what could be the reason of this knee pain/joints pain no swelling just feel loose n painful?

Something systemic? Bilateral knee pain and thyroid problems doesn't ring any bells but at your age it does suggest you be worked up for something systemic going on. I would look for markers of general inflammation in your blood and might even consider looking for an auto-immune etiology if nothing apparent on physical exam. There are even some viruses that can cause transient arthralgias.