Hello, Thank you for asking your query at DoctorSpring.

From your symptoms of painful black dot on tip of penis, could be Herpes. The major mode of contracting herpes is sexually, anal sex in specific. But, since you are telling me that you are not sexually active, you could have acquired through bad hygiene like sharing undergarments etc.

There is nothing to shy away about this. You can talk to your parents about it and explain to them that you are quiet anxious about it. You have got to follow some hygienic practices like, washing regularly, don't use public toilets as these places are not clean and carry a lot of infections, do not share or use anybody else's undergarments, this is common in hostels.

You need to consult a physician, to do few blood tests to confirm if you are having herpes and start treatment

Hope this helps. Please feel free to ask follow-up questions