Should I push for tests for Sjögren's?

The past few months I’ve had swollen lumps along my jaw on the right, can feel on the left too but not as bad.

GP sent me for an ultrasound which said lymph nodes were all fine.

But I just found out about Sjögren's today and I’m wondering why they didn’t ask me any questions about dryness, fatigue etc, or why they didn’t do tests for that.

I have a lot of symptoms that could be Sjögren's and I’d like to rule it out more than anything.

I’m in the UK. What do I need to ask from my GP? Can they request tests or do I need a referral? Thanks