I just noticed an indentation in my middle finger near the nail bed.

Hello and welcome to EmpowHer,
Dents in figure nails can signify several conditions:
--iron-deficiency anaemia: a reduced number of red blood cells due to a lack of iron in the body
--haemochromatosis: the body contains too much iron
--Raynaud’s disease: a common condition affecting the blood supply to the fingers and toes, causing them to turn white
--lupus erythematosus: an uncommon condition where the immune system attacks the body's cells, tissues and organs

Pinting indents can indicate:
--psoriasis: 10%-50% of patients with psoriasis have pitted nails
--eczema: a long-term skin condition
--reactive arthritis: where the immune system attacks the joints, muscles and other parts of the body following an infection

These condition are less common.
If the dent becomes deeper or it appears in more fingernails, you should see a doctor.
Faith