Would this be rare?

The second is a complication of the first. TNF-α inhibitors used for their treatment probably accelerated the occurrence of breast cancer. It can happen. Sorry that you are experiencing this.

??? this is what I know,

I had eye issues
I went to the eye dr,
he sent me to a specialist
He sent me to a top specialist
that 3rd dr found out my blood pressure was through the roof
I went to the ER,
They found out my kidneys were failing.

Yes

sounds like something bigger is happening, regular arthritis is no big deal, but Rhumetoid arthritis can be a part of something bigger

Sure