So, I noticed yesterday that there is a random spot of extremely sensitive skin on my arm. I use moisturizers so it I highly doubt it's dry skin. What should I do?
People often develop these extremely sensitive patches of skin and just live with them. Its called allodynia.
If it spreads or you notice other patches of skin becoming super sensitive you should see your doctor.
If the patch you are describing becomes so sensitive it is painful to even put clothes on then also do see your doctor.
It could also gradually calm down and go back to normal.