Our skin is very rich in blood vessels to keep it viable, and injuries to such blood vessels are very likely, especially considering it is organ that shields us from the outside environment. That’s why we have a system of bleeding control called hemostasis. Hemostasis is complex and relies on your vessels contracting following injury, your platelets adhering to the defect to plug it and your coagulation system activating. Any defect of such components can cause a variety of manifestations from mildly symptomatic bleeding after moderate trauma to spontaneous bleeding. The skin shows various manifestations depending on the system affected.
If your platelets are reduced or non-functional, small minute bleeding can occur on the inside of the skin causing slightly raised red spots measuring a few millimeters. They are found more commonly on the extremities since they are more liable for trauma, but they can also be found on the trunk. Associated manifestations include bleeding from your gums or vagina and blood in your urine or stool. If the cause is severe enough like immune thrombocytopenia, and your platelet count falls beyond a certain value, you will bleed into your cranial cavity -the part of your skull which houses your brain- and this can be fatal. The main differentiating characteristic is that these dots don’t fade if you press on them owing to them not being a sign of “inflammation” but a type of bleeding.