Thanks for the query,
Probably you are having a low platelet,
Minimal trauma is obvious during sexual intercourse.
Specially in the groin area.
You dont need to worry musch, just get platelet levels checked.
Please meet a dermatologist
for exact treatment.
Let me know if you have any other doubt.
you can ask a direct question to me on this forum, following the below link.
Wishing you a good health.