You should call your doctor if you think a sore is forming. Mild damage causes the skin to be discolored, but a sore doesn't form. In light-skinned people, the damaged skin may turn dark purple or red. In dark-skinned people, the area may become darker than normal. The area of damaged skin may also feel warmer than the surrounding skin.
Deep sores can go down into the muscle, or even to the bone.
If pressure sores are not treated properly, they can become infected. An infection in a pressure sore can be serious. Pressure sores also hurt a lot and make it hard for a person to move around. Anyone who sits or lies in one position for a long time might get pressure sores. You are more likely to get pressure sores if you use a wheelchair or spend most of your time in bed.