Hi Dear thanks for your question,you have a deep cut in your inner vagina that is labia minora
and you think it is due to in adequate lubrication during sex ,Dear you right it i could be trauma in the form of bruise, and has got infected it cannot be in growth of hair ,as there are no hairs on labia minora..cortisone
is wrong treatment, neosporin
ointment is ok ,continue it and mean while take systemic antibiotic in the form of leofloxicin,i think it will be ok in a week time,if not so consult gynecologist,there may be abscess
which may need drainage
,hope i addressed you question,for any further query welcome to health care Magic.