I have been experiencing this strange sensation in my left leg - the best way I can describe is, this tingling dull electric shock running from my inner knee upper part of my leg.

Sciatica refers to pain, weakness, numbness, or tingling in the leg. It is caused by injury or to pressure on the sciatic nerve. Sciatica is a symptom of another medical illness, not a medical on its own. Sciatica occurs when there is pressure or damage to the sciatic nerve.
I'm looking for a answer on what is causing this, it is sciatica, or nerve damage? Or both?
P.S. I'll get back on this one.