A scratch on the skin with a pen tip forms a lump?

I am white and some parts of my skin are very sensitive. I think my problem is serious. I live in the interior and I do not have a dermatologist here. if you make a scratch on my skin with the tip of a pen it will rise in the form of a calf and sometimes appear small balls as if it had bloated the skin that disappear after a half hour. I would like a diagnosis online that his to know if it is not related to blood problems. Please . Thank you!
Expert answer:

In fact what you have is an increased sensitivity in the skin, which by its description is of "allergic" origin. The causes can be numerous, including may be related to emotional factors and is not usually severe.

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