Hi Dear !! Thanks for your query to HCM.
I reviewed facts of your query in context to your health issues.
My Opinion-
In My opinion, in the given situation you have -post-shaving folliculitis- if you have shaved it lately/ or
it could be from low grade bacterial 
skin infection in private parts
Other cause-like fungal  infection - needs to be ruled out with your doctor and if needed with 
Dermatologist.
Don't worry for 
STD, as you don't have positive history of contact.
Do's Suggested-
Keep private parts, clean with dettols sponging to control low infection.
Use loose Ugies.
Take 
ibuprofen with script from your doctor.
Take Antibiotics  if no relief in 3 days time with ibuprofen.  
Next appointment-
After 2 weeks to review treatment for existing stomach problem .
If you update more information/ details upon these suggestions,I would give further suggestions on medicines  to correct your health issues.
If need be, update any health issue 24 x 7 by a direct question to ME, at following HCM link-http://doctor.healthcaremagic.com/Funnel?page=askDoctorDirectly&docId=70229 
Dear,if you don't have any further query  in this regard, Do close this query with YOUR pleasing and feedback comments to rate this reply and service, to boost the morale of incoming Emergency patients like YOU, at HCM services. 
If you want to update more details and ask more update queries , 
You are most Welcome herewith !! 
Good Day!! 
Wishing Good Healthy Life in time to come!! 
Dr.Savaskar M.N. 
Senior Surgical Specialist 
M.S.Genl-CVTS