Actually, May 12 is also considered to be Awareness Day for ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome), Gulf War Syndrome, and that whole group of neuroendrocrineimmnue illnesses. The National Fibromyalgia Association has done such a good job of publicizing the FM aspect of Awareness Day, that sometimes people don't realize the other illnesses are also part of the May 12 Awareness Day observance.
I don't, however, know of an awareness day for chronic pain. We certainly could use one! It would help to educate doctors, government agencies and people in general on what it's like to live in chronic pain and what treatment options are needed. Great idea!