Sciatica? am i too young?

I am now 20 yrs old and i've been suffering with what i think is sciatica since i was 18. slight pain from my lower back.. to very uncomfortable pain on my ocks,down to my knee, leg and my ankle. ..but then I would just get terrible pangs on the bottom of my foot and it felt like my entire foot was burning/ being electrically shocked. AFter that, I started noticing jumping or hopping..my ankle would just weaken and hurt as i hit the ground. am i'm talking like jumping over a puddle...or from the sidewalk to the ground. The sciatica went away for some time...but now its back. Am I too young to worry about this? Is it because I'm working out? (my abs mostly)