Hi Karla,
I can relate to your pain, as I also have had and am having pain in the back of my left leg. It's either in my calf or behind the knee, and hurts bad, when I'm walking it feels very tight like the muscle is stretched, sometimes when I'm sitting i get shooting pains as well., like nerve pains. Is this similar to what you are experiencing?
I've had an mri and know that I have a bulging disk and a lot of back issues, so my doctor said it's sciatica. I have to go with that diagnosis, since I don't know what else it could be. Nothing helps the pain though, and I am open to suggestions.
I've had it pretty much since April, and it's tough to live with.
I hope you can get some relief and or answers soon. Do you have a good back doctor you're seeing or have you had any tests or x-rays done?