At first, don't be worried. You are supposed to know that it's quite normal for many people to see stars when they do cartwheels. There is a scientific explanation. When you do some cartwheels, the blood would flow from the capillaries back into the brain, which might press the visual nerves even give rise to encephalemia. And after you stand up on your feet again, a transient inadequacy of hematic offering to the head happens, thus it's natural to see stars or light spots with colors. However, this symptom is a instances of a issue, you might have an anaemia in fact. Therefore, i suggest that you should go to see a doctor and have a physical examination to make sure whether you are in good condition. Hope you accept my proposal.
