See a doctor, preferably a primary care clinician or rheumatologist
Review symptoms and medical history
Get a physical examination
Ask for blood tests
Complete a complete blood count
Complete a comprehensive metabolic panel
Check inflammatory markers such as ESR and CRP
Test for antinuclear antibodies
Test for specific autoantibodies based on symptoms
Test for rheumatoid factor
Test for anti-CCP antibodies
Test for thyroid antibodies
Test for complement levels
Get urine tests if kidney involvement is suspected
Get imaging tests if joints or organs are affected
Consider biopsy if needed
Rule out infections and other conditions
Follow up with a specialist for interpretation and diagnosis