Hi aimtoothpaste (love that -lol);
In answer to your question, YES there is such a thing as Mild Lupus. I, at this point in my life, have been downgraded to Mild Lupus (however, I have a sever case of Fibromyalgia). For most of us with Mild Lupus, we are able to manage our disease without having to take a lot of medications.
It is quite apparent that your current physician does not have a lot of knowledge about Lupus and its myriad of forms and how it affects each of us differently. So, it might be in your best interest to start looking for a rheumatologist who is up to date on Lupus and its treatments. If this is too difficult to do, then I suggest that you educate yourself about Lupus (and/or auto-immune - connective tissue diseases) and that you INSIST that you doctor continue to run tests, learn about these issues, and provide appropriate treatment.
I am a strong believer that we must be our own health advocates and that we must make informed decisions about our health care. Those decisions include mandating that your physician do what is best for your health and that he/she do everything that they can to provide you with answers and treatment.
You are not crazy! Your symptoms definitely sound like those of some type of auto-immune issue (of which there are more than 60) and, as Nonna so aptly pointed out, one round of tests is not enough to confirm or deny the presence of an auto-immune disorder.
I wish you the very best and please know that we are here for you.
Peace and Blessings
Look For The Good and Praise It!