Last week's ER visit included a bunch of extra blood samples for a rheumatologist. It's hard to get one to see you without a recommendation. The doctor at the ER, this time, is the first to make that recommendation.
Yes keep going! It is hard to see one and have it covered under your insurance, but in America (if you are in the US) you can just pay out of pocket if your insurance doesn't cover it, or requires several hoops to jump through in order to get a referral.
You can also ask your primary care doctor to give you a referral. Most will oblige.
Out of pocket, the fee is probably a few hundred dollars for an hour consultation.