I'm curious about this red spot under the skin of my fingernail (photo attached)

Based on the image and your description, the spot on your nail could be a few things. Let's explore some possibilities: * Splinter Hemorrhage: This is likely a small blood vessel that has broken under the nail. It can appear as a small red or brown line or dot. Trauma to the nail is the most common cause, even minor bumps you might not remember. These are usually harmless and will grow out with the nail. * Nail Matrix Nevus (Mole): While less likely given the appearance, it's possible it's a mole within the nail matrix (where the nail grows from). These appear as longitudinal pigmented bands in the nail. The darkening with pressure is not typical for a mole. * Subungual Hematoma: This is blood trapped under the nail, usually from an injury. However, you mentioned no pain, which makes this less likely. Hematomas can sometimes appear as dark spots. Recommendations: 1. Monitor It: Since it's painless, start by simply observing the spot for a few weeks. See if it grows out with the nail. If it does, it's likely a splinter hemorrhage and nothing to worry about. 2. Note Changes: If the spot changes in size, shape, color, or becomes painful, it warrants further investigation. 3. Risk Factors: Do you have a history of melanoma? Melanoma under the nail is rare but can occur. Disclaimer: This information is for general knowledge only and doesn't substitute professional medical advice. If concerned, consult a doctor or dermatologist for a proper diagnosis.