I have a sharp pain that begins on my left buttocks every time i try to reach for my toes and shoots down my thigh, what is the problem?

Sciatica: Sounds like sciatica. This condition is usually responsive to rest and over the counter anti-inflammatories. If fever exist however, then you need medical evaluation. Any persistent pain for more than 3 weeks also warrants evaluation. If you wear wallet in rear pocket on that side remove it.

Searing heat.: Your symptoms certainly sound like you have irritated your sciatic nerve. Rest and anti inflammatory medications may help but ultimately you may have to see a specialist.