If you post your symptoms, we may be able to help a little more. But if you arrived at this site after your own research, then you must have some sypmtoms consistent with lupus. You could request the doctor run just the ANA test, hopefully that wouldn't be too expensive and it would help by "ruling in" some autoimmune disease as a possibility if it were to turn up positive.
You could try a large teaching hospital for care as well - usually they have indigent care programs where they are reimbursed by the state for care given to uninsured people with few monetary resources. Some charities may be able to help you as well; there are social workers that could help guide you where to go as well within the Salvation Army for example. (I assume you are in the US though with these suggestions).
As to suggestions for your illness, has hemachromatosis been considered?
It's the only disorder I know of (I'm not a medical person!) that results in too much iron being in the blood. You could also be taking in too much iron with diet/supplements. Symptoms of this disease can easily resemble those of lupus. (Blood tests can determine whether the amount of iron stored in the body is too high with the transferrin saturation test --- a result higher than 45 percent are considered too high.)
Good luck to you - I hope you find someone that can help with diagnosis/treatment at little to no cost.