LOWER BACK PAIN ON LEFT SIDE

I am experiencing severe pain in the lower left side of my back.  It hurts when I am sitting, and it also hurts sometimes when I am walking.  Sometimes it is a stabbing pain right at the top of my left buttock (in other words, between the lower back and upper part of my buttock).

[TrudieC]

It is possible your sciatica is causing issues.  It is important to find the cause so you should see a doctor and arrange for exrays and an examination.  In the mean time you might get relief from taking aspirin or ibuprofen and try this stretch:

Sit straight up on a chair.  Place your left ankle across your right knee with your left knee sticking out to the side.  Press down on your left knee while arching your back and hold.  It really helps.