Hi Dollydee
What you must remember is "it's not what illness you have, but how that affects your daily life".
I began to have problems in 2000, when i developed shingles. It took 8 years to discover what was wrong with me, but I was awarded DLA in 2003, and have had it renewed twice since, and since 2008, I have been given HRM and HRC indefinitely.
Don't say things like "I have a lot of pain" etc, just explain how the pain stops you doing things.
I was diagnosed with Fibromyalgia in Oct/Nov 2008, and all my awards have been given before any diagnosis! I also have Osteoporosis, Osteoarthritis, Asthma and I have LOW Blood Pressure.
Good Luck!