pain imy calf running up to my thigh

i have been suffering with this pain for a couple of months i have had siatica in the past but this does not feel like that it is worse when i first wake up i could scream in pain my calf feels like it is on fire and it runs up to my thigh and the back of my knee it like someone is sqeezing my leg and i have sharp pains runnin through it i take painkillers and eventhough it doesnt go completely as the day goes on it turns into a dull ache and if i put my leg in a sertain posistion i have a sharp pain which makes me scream out and lately ive noticed pins and needles sometimes in my foot its like a mixture of cramp and sharpe pain running up my leg,, any answers veronica