Hi there, I don't have fibro but I was obese and drastically out of shape when I first started losing weight, so I can relate in that sense! My advice is definitely to start out slowly and yes, walking 10-15 minutes at a time can definitely help!
Have you seen this website:
http://www.fibromyalgiaexercise.net/
This seems like another good article:
http://www.fmaware.org/site/News2?pa...rticle&id=5269
Anyway, you will get there! It may take some time but it's worth figuring what is ok and what makes you feel worse in terms of pain. I am not sure if it's affordable, but it may be worth working with a physical therapist or occupational therapist who understands fibromyalgia and can teach you some effective exercises, too. Good luck!