Fitness Goals Support Group
This community is dedicated to group support around achieving fitness goals, whatever they may be, through personal training, athletic activites, or other strenuous activity. Whether you are trying to get fit to treat a health problem, boost your mood, relieve stress, or tone your body, this group is a great place to meet other like-minded people who have similar goals.

Sciatica is often misdiagnosed. Pain is often misunderstood, it is complicated and will require more than just your GP.
I highly recommend seeing someone who specializes in muscle pains (often you can find a trainer even at the local gym who could help you and show you exercises to improve strength...) and work with them to find out exactly what is going on and how to correct it.
Also, I'm sorry you are going through this I have the same type of pain. There are a lot of muscle groups involved for me in a lot of places and I tend to make it worse with my bad habits. I have not been able to go to a physiotherapist (I've been to everyone else though, dr's and xrays and chiropractor and there is a guy who owns a gym who can help me when I am ready), I study at home and do what I can for now. Building strength and learning to breathe correctly and trying not to stop going. Even though lying down is the only way to escape the pain sometimes and even then it is not 100% gone. *hugs*