Thank you for asking your query at DoctorSpring.
The lesion over the penis is NOT likely to be Herpes. The rapidity of onset and the fact that there are bugs/ insects and you were sleeping naked favour the possibility of an insect bite or irritant contact dermatitis rather than Herpes. Even though the particular lesion is not typical of herpes, herpes can have different types of presentation. If not for the above facts a Herpes lesion could be suspected. There is no need to worry. No particular treatment is needed at this point of time. If the lesion persists beyond a week and/or if there are new lesions or symptoms further evaluation might be needed.
Sleeping naked is not ideal for jock itch treatment. There is more chance of friction and further damage. Moreover sweat and moisture can occur between the legs, which can impair the clearance of fungi. The best would be to use cotton underwear. Cotton will absorb the extra moisture and keeps the area dry.
Hope this helps
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