Ok, it seems that there is something wrong with your eyes. So, as you can see, black eyes underneath is a sign of health proble, which might be resulted from a lack of sleep, bad use of your eyes, staying up late, or some bad habits. Since those habits could damage your body and black eyes could be a signal of your problem, which needs to be examined in the hospital so you can know what you do to fix the problem.
You may get the dark circles under the eyes because of the lack of sleep and bad blood circulation. You should keep notice of the good diet and good rest. You could do these two main things well. You could also eat more food with vitamin C to moisture the eyes. In addition, you could also exercise to make your blood circulation go on well.
There are many reasons for dark circles under eyes. The no. 1 cause should be poor sleeping. Poor sleeping will lead to a pale skin without lutre, which makes the dark circles more visible than ever. As to other conditions which might lead to dark circles, there are many to state. Allergies of skin around eyes can make dark circles. Skin around eyes is thin and fragile. Allergy will have the capillaries under skin get broken and swollen, and here are the dark circles. Other causes include nasal congestion, smoking, dehydration from insufficient water, too much caffeine or alcohol, vitamin deficiency, bad nutrition and iron deficiency. Besides, people with dark skin toner are more easily to get dark circles because of excess melanin in skin. I am not sure about the exact reason which triggered your dark circles. You could check all these causes introduce above and see if any fit your situation. If it is short term symptoms, I suggest you to take good sleeping, drink more water, take some vitamin supplement and do some natural mask and massages. You can do all of these at home, which are easy and convenient. If your dark circles are serious and constant situation, I suggest you to consult your doctor for detailed examination and professional direction to avoid any serious condition associated with kidney or other problem. Wish you good luck.