| What do you mean by "below the skin of my penis," please? Also, where is the redness located?
I'm not trying to set you up for a possible diagnosis here. Doing that would be irresponsible of anyone here without first examining you, even if they were a doctor. When in doubt, and in order to ease your worries, it is best to consult a physician.
We can however, point you in a direction where you might find information that would be of help for you as to the possible causes of the condition about which you are complaining.
You might also like to try clicking on links to questions that have been similar to yours on the bottom of this page. Maybe you will find some helpful information there. | 
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