1 If you add music and files to your iPod while you are charging the battery, it will take longer for it to charge. 2  Before using your iPod nano for the first time, it is important that you let it charge for a minimum of three hours. 3  If you do not, you can weaken the battery, giving it a shorter lifespan.
There is also a chance that your black period blood is caused by an infection or STD. Uterus infections can cause blackening as well as many STDs. Women that have sex during their cycle also experience black bleeding because the blood was pushed back into the vagina and can become trapped as a result.
Certain medications can also lead to black-colored stools. Iron supplements and bismuth-based medications, for example, can darken your stools. Sometimes, serious blood and circulation abnormalities in your digestive system can cause black, tarry stools. These can include the following: Bowel ischemia is a reduction of blood flow to the intestines. Vascular malformation is misshapen veins. Varices are large, protruding veins in the intestines.