Just a side comment. Renal failure is the top killer in captive iguanas.. well that and pet shops and the horrible advice given.. I am fairly confident your ig is in mating season.. iguanas live 2-3 decades in the wild.. people often times are unaware that feeding rats mice bugs etc ultimately leads to premature renal failure.. there are plenty of rehabbers on this thread that will agree to this. Personally I would want a vet exam done.. they can do physical exam, feel for any hard organs etc. A blood chart would give you a better gauge on the iguanas health.
As for the mating season guess.. try to keep the iguana unexposed to household traffic and lower its light schedule a bit. If it becomes an issue where the iguana is overly agressive and harming itself then you can try to trick its little brain out if mating season by complete darkness for a few days even a week. Naturally keep it warm.