What Is The Heaviness And Tingling In Sciatica Diagnosed Leg?

I have been diagnosed with sciatica by my doctor about 2 weeks ago. There was no MRI, just diagnosed based on my symptoms (extreme pain in my leg and low back). The last couple days I have had "heavy legs". They feel heavy, and my left leg which is the leg I have sciatica in, also feels tingly. Can this be a sign of something more serious?