I had to jump into this conversation, I can't not to share with you my own experience and I hope it will help you somewhat.
I was Dx with Juvenile RA when I was 12. I had some mild treatments and than moved from my Dr and never went for many years to see anyone.
In my 30th I started to develop symptoms which ruled my life. I went to see RA in this area... One after another - all 4 of them told me I am OK and I don't have RA and this is only Fibromyologa and OA so Celebrex is your medicine.
I went with it for about 10 years being tired to go from Dr to Dr and see their careless faces; I decided to quit spending my money on them.
After I had 2 major spinal fusions, became disabled and was sent to PM, my PM Dr told me that he wants me to see this wonderful RA Dr at *** in NYC.
After 2 hours evaluation, she told me that I just was Dx with severe, far gone RA and need to start medication right the way, otherwise damages in my body will continue.
Meanwhile my blood work came back normal. She wasn't surprise at all. She told me that this is not uncommon to have very symptomatic patient and blood work doesn't show anything and V.V.
It takes really good specialist, very knowledgeable one to Dx you with RA. Many of them afraid or just don't care to go further with testings, evaluations if your blood work came back normal. Done this, been there.
I am very blessed to have this wonderful DR. Not only that I was Dx with RA, but also with MS and Lupus. Now I am on medications, I am doing better.
I am very positive person, but I am very upset with other Doctors who I went for help. I am upset only because they did not take time, they did not have enough knowledge to Dx me on time. By the time I was Dx by my wonderful RA Dr, I have fluid in my lungs and enlarged lymph nodes; torn tendons, ruptures in ligaments and muscles. I continued working, using my body a lot not knowing that beside severe pain all over my body, I continue injuring myself in a gym and by daily strenuous work where to pick a pat of water could cause tears and ruptures of the muscles and ligaments.
I have an advice from the bottom of my heart for those who know something is wrong, who is in pain and Doctors who they go to see - completely ignore them and their issues: CHANGE YOUR DOCTOR.
Don't even hesitate to go and search for a good Doctor. One more advice: if I went to see new Doctor in same area, I did not tell new Dr about going somewhere else. The thing is: they know each other and don't want to controversy another opinion. Do not tell your new Dr that someone else couldn't find anything, b/c you will get another: I think nothing is wrong with you. I learned this in a hard way.
Best of luck to you!

Moldova