Hi Olivia,
Well, from the description of your joint pain being so fleeting and moving around, very random, that screamed Fibromyalgia. Lupus joint pain doesn't move around like that. It stays put in one or more places. Lupus joint pain is a form of arthritis. So on a bone scan it will show up. Fibro joint pain is not arthritic. In fact the pain is not actually IN the joints. It's the muscles, tendons, ligaments that surround the joints that is causing pain. On a bone scan, your joints will look perfectly normal. A bone scan would be a very good test to have done. It will tell an awful lot about what is going on.
The rib/upper back pain you're having could be pleurisy, but it would show up on a chest xray. Pleurisy also doesn't really make your back hurt (in most cases). You feel it in your chest, your lungs, in the front. In Fibro, rib/chest/back pain like you described is called Costochondritis. It can be horribly painful and excruciating when you take a deep breath in. I get this, and it's awful.
Rashes. They can be present in Fibro as well. You can also have a very slight redness to your cheeks with Fibro, but not the full blown lupus butterfly rash.
Your ANA can change often. The test is a snapshot of what it's doing right now. It can be negative one moment and positive the next. Why doctors run this is that they want to see how high it actually is. A very high positive ANA is a good indicator that something AI is going on. However, you can have a negative ANA and still have lupus. Mine is negative right now. But my lupus is very quiet too.
If all of your labs are coming back normal, your rheumy should test you for Fibro. Fibro will present normal blood work. He/she will do a physical exam and take note of all your symptoms. There are no blood tests for Fibro.
I hope this helps Olivia. It's good to keep more than just Lupus as the possibility. So many diseases mimick lupus and fibro, and they both mimick each other. It's so frustrating. One of the reasons why it can take so long to get a diangosis.
I would take a picture of your hand rash and any other rashes you get. Just in case they disappear before your appointment.
Keep us posted and take it easy. I know this is hard. We're here for you!
Ginny