Anyone with vast info on skin cancer please give advice about a mole...?

Unfortunately I am one of the many American's without health insurance at this time, and thanks to our economy, I am pretty broke too. Thus I really don't want to go to a doctor unless I really have to. I have a lot of moles on my body. Recently one on my back has been itching very bad, all the TIME! My husband has been watching it for me, he says for all he can remember, it has not changed in shape, size or symmetry. It still looks like it always has. We have compared it to pictures on the web and it looks fine. So the only issue is the constant itching. Should I worry? Should I go ahead and go to the dr? All my other moles are fine.