It could be deficiency of Vit
B12/D3...
Also get tested for Rheumatoid Arthritis. Anti CCP Antibody testing.
If the fingers, are cold check for blood circulation in fingertips.
If tingling sensation in fingers, rule out carpal tunnel syndrome too.
Next Steps
Test for Vit
B12 and D3 deficiency.
Health Tips
Avoid taking medicines that are secreted in breast milk and be harmful to the baby.