Many people have a similar phenomenon. If you are not at ease, you can see a doctor. The following is for reference.
Look at health from the color of lips
Black lips:
Digestive system abnormalities: loss of appetite, constipation, diarrhea, abdominal distension, and black lips.
Black deposits and dark spots appear, which may be chronic adrenal cortical hypofunction or digestive tract polyps, or syphilis.
People with black lips or purple-black spots may lack vitamin C.
Blue lips:
Because of poor blood circulation, it is prone to heart disease, anemia and stroke.
When it is extremely cold, the blood circulation at the end of the body is not smooth and the lips are blue.
Crimson lips:
When you have a fever, your lips are crimson. ... explain
Heart failure, lack of oxygen or lung disease can make your lips blush.
Lip color is red and purple-if there is no fever or carbon monoxide poisoning, there may be problems such as heart disease, lung disease and heart weakness.
If the lip color is black and red, it is mostly because there is a problem with the large intestine, as well as symptoms such as poor throat and otorhinorrhea.