What Could Throbbing Pain Below The Elbow With On And Off Pain In Legs Indicate?

Hi last night i was in agony. I had a really extreme throbbing pain from the elbow down. The only way to describe the pain was if somebody had tied an elastic band really tightly around my arm and didnt let go. That kind of throbbing. It was so bad that i was in tears. I have been diagnosed with carpal tunnel syndrome during pregnancy but had NEVER felt pain like this before in my arms but do occasionally have the dame pain down my legs sometimes.. any ideas as to what this could be? The arm pain is slightly still there today but not half the pain...