A red dot is usually a sympthom of an insect bite. The red circle is usually an infection from that bite. Disinfect it and put an ice pack on it and if it doesn't get better, call your doctor.
Cool
It could be ringworm.
Cancer Cancer
The flag of Greenland has a white stripe, a red stripe, and a red and white circle.
If its just one Red spot with a white ring it could be a ringworm.http://www.webmd.com/skin-problems-and-treatments/tc/ringworm-of-the-skin-topic-overview
A large, purplish-red circle on the skin. Caused by the leakage of blood out of a vessel and under the skin.
It is white with a large red circle in the middle. The red circle is said to represent the sun.
The Bangladesh flag consists of a red circle on a green base. The circle is placed slightly to the left side of the Bangladesh flag so when the flag is flying on a mast the circle will appear to be in the center.
A white circle with a red dot in the center often symbolizes the Japanese flag, representing the sun. In various contexts, it can also denote a target or an indicator of focus. Additionally, it may appear in design and branding to suggest simplicity and clarity, or in certain cultural contexts to convey specific meanings.
A red circle on your skin. See the related link for a photo.
Go slow but when you get to the red dot just plan out what you r going to do before you go on the red dot.
The big red dot is a storm.