Been Hypothyroid for over 10 years, then dx'ed with RA, now have Hashi's- ??

Hi all, I usually post to the fibro and RA boards on here because that was what I was previously diagnosed with. Over 10 years ago, I was dx'ed with hypothyroid, and I take Levoxyl. During all 3 of my pregnancies, my thyroid would go out of whack, and the doc would adjust the meds, and it would all be okay. The I was dx'ed with fibro, which I am positive I have, since 1 GP and 2 different Rheumys diagnosed. A few years ago, I started having a lot of joint pain, especially in my finger joints. Not a lot of swelling, some stiffness. In the winter time it got really bad, my hands hurt so bad that I could barely do things like open jars, zip a coat, turn a doorknob, etc. Even typing on the computer would hurt sometimes. My rheum at the time kept testing for RA and it would come up negative. My thyroid tests were always within normal range. My rheumy said that I was "probably" sero-negative RA, where you have RA but it just doesn't show up on blood tests. I was taking Lyrica for fibro and Plaquenil for the RA. I started to have some swelling of the fingers, especially the MCP joints. I was having other issues too, like sun sensitivity, dry eyes, mouth sores, dry mouth, so the doctor tested me for Lupus, which was negative, and said, "You probably have Sjogren's as well." I was starting to become dissatisfied with this rheum, because I would go into her office tell her I was in pain and she would put my on a prescription NSAID, which would only work for about a week, and then stop.I have probably tried like 10 different NSAIDs, and I was like "Give me something else!" She tried to give me an herbal supplement that she said "may or may not work, and it's kind of hard to find, and expensive" which I didn't take. My fingers have been slowly becoming deformed over the years, and she told me "Everyone's fingers become bent as they get older." Hello, I'm only 41!! I decided to stop seeing her because she was not on my insurance and and office copay was like $160, and my husband put his foot down and said, "We *cannot* afford those payments anymore, find someone in-network.
So I found a new rheumy and have seen her a couple times. There was a couple of months between my last visit with the old rheumy and the new one, and I was going through a phase where I was feeling nauseous a lot and having trouble swallowing pills. My thyroid pills are these little powdery things that turn to dust in the back of your throat if you don't swallow them quick, and so for about a month, I wasn't taking my thyroid medicine regularly. Then I saw the new rheumy and she did lots of detailed tests. According to the tests, I don't have Lupus, Sjogren's, or RA, but I do have Hashimoto's Thyroiditis. She said that Hashi's can mimic a lot of signs of RA, like the joint pain and swelling. My question is, all the time I was having the joint pain in months past, my thyroid tests were normal (I think my GP always ordered TSH, T3 and T4). Could it have been that the Hashi's was kind of "on the back burner" and now it has become active because I stopped taking my meds for a while?

I'm seeing an Endocronologist on friday, if anyone can think of any questions to ask, let me know. Please let me know what you think about my post, I know you are not supposed to give out medical advice and that's not what I'm looking for, just if anyone has had the same experience as me (hypo for years and then Hashi's).
An interesting side note- I am allergic to Synthroid, I think I am allergic to the acacia in it that is used as a filler. I broke out in hives when I took it, and so I went through all the meds I was taking at the time and figured out that acacia was the only thing different in all my meds. Thanks for reading!