constant burning/tingling discomfort in penis without infection

my 17 year old son has been complaining of penis discomfort with a burning/tingling sort of pain for several months. he complains of worsening discomfort after he showers. he is not sexually active so there is not a concern for an STD. he has seen the dr. who did not find an infection but blood tests revealed a high acid count. i had read in a forum that lack of calcium could cause problems in this area. it is possible that he does not get enough calcium. he has so much discomfort that he rarely leaves the house. i am really worried and would like to know what could be causing this problem. he is at the point where he believes he will have this problem always. please help.