Autoimmune - Advice?

So my therapist recently suggested that I (23f) attempt to connect with fellow people dealing with chronic illness (particularly in the realm of autoimmune diseases/disorders) because of the frustration that I'm currently dealing with pertaining to my symptoms, potential diagnoses, etc.

Anyway - here's the situation. After almost four years of experiencing a sudden onset of symptoms - such as tachycardia, dyspnea on exertion/feeling like I can't get a deep enough breath, unexplained weight gain, excessive sweating/inability to regulate temperature, more recently some upper back pain and cracking joints, general fatigue, etc. - I'm finally in a place where I have a decent enough job and health insurance that I was able to get a rheumatology referral.

I went to the rheumatologist, and, after speaking with her for all of ten minutes, she told me she didn't have a very high suspicion of any autoimmune disorders. And as the blood tests that we did that day started coming back normal one at a time, that initially seemed like a fair assessment. Totally in-range thyroid, rheumatoid factor, CMP (except for ever-so-slightly low Carbon Dioxide, but I was told not to worry about that since it was barely out of range), C Reactive Protein, Sed Rate, and CBC+PLT+DIFF. But then my AntiCCP came back through the roof. For reference, a negative AntiCCP would be less than 20 units, and a "strong positive" would be anything greater than 59 or so. Mine was 133. In short, we're now looking at Rheumatoid Arthritis.

Honestly, at first, I was actually rather relieved that we at least had a lead. I'd been diagnosed with dysautonomia and IST at my cardiologist a little over a year ago, and my pulmonologist and I discovered about nine months ago that my windpipe is very narrow; but we couldn't really determine a reason why for any of these things. So I thought that maybe RA could be an explanation. But now I have all my specialists telling me that they don't really know if RA would be causing my specific symptoms or not, since RA is more about joint inflammation (from my current understanding).

In terms of testing I've already done, all my EKGs/ECGs always come back clear. My latest exercise stress test was technically fine (even though I felt like I was dying the whole time) - I just had diminished exercise capacity, increased wall motion, and my left ventricular wall segments showed thickening. A chest x-ray I had a while ago showed clear lungs. I just recently did x-rays of my hands and wrists, and there's no joint erosion so far. I did a PFT with pulmonology last year, which is how we found out about my airway being narrow; and I just did a repeat PFT that I'm currently waiting on results for. I'm also waiting on results for a sleep apnea study (if this is relevant, my left leg has been Charlie-horsing quite frequently lately, especially in the middle of the night). I've had a tilt table test done and it was normal, so this probably isn't POTS.

Also, I don't know if this is important, but I run out of breath/sweat very easily even when doing mundane tasks like dishes. Going up stairs is especially difficult, even just a single flight. Movement makes me feel overheated, even in the winter. I'm currently on a beta blocker, but my heart rate still gets higher than I would like when I'm moving at all.

Since I'm already in the thick of medical things, I want to ask my rheumatologist for some follow-up tests to rule out any other possible autoimmune disorders, because I want to make sure we're covering all our bases, since the ways in which my body is malfunctioning on a daily basis still don't make total sense to me. I've been doing some research and thought about asking about myositis, but I'm just not completely confident in advocating for myself at this point, since I feel like I still don't really know anything. I'm also wondering if y'all have any other suggestions for other possible problems I could pursue asking about? I'm just confused and stressed out and a little sad.

If you stayed this far - thanks for listening.