It could be eczema, sweat dermatitis, allergic reactions or eczema.
You need to wash the areas several times with fresh water. Do not use any cosmetic products at the sites.
Apply calamine lotion at the site of the lesions and see if it helps. You could take some oral antihistamine medications like cetrizine or loratadine. You need to maintain a good personal hygiene .
Anti-itch drugs, often antihistamine, may reduce the itch during a flare up of eczema, and the reduced scratching in turn reduces damage and irritation to the skin.
For mild-moderate eczema a weak steroid may be used (e.g. hydrocortisone or desonide), whilst more severe cases require a higher-potency steroid (e.g. clobetasol propionate, fluocinonide).
Eczema can be exacerbated by dryness of the skin. Moisturizing is one of the most important self-care treatments for sufferers of eczema. Keeping the affected area moistened can promote skin healing and relief of symptoms.
http://en.wikipedia.org/wiki/Eczema
Let us know if you need any further information.
It would be advisable to consult a skin specialist for your symptoms and a proper clinical examination.
Let us know if you need any other information and post us on how you are doing.
Regards
Yo! im having the same probelm bro. I also have that on my inner thighs. Sometimes i get these really knotty like bumps under my skin, and if popped they bleed. I also have that white build-up stuff in the hair follicles on my inner thighs and scrotum. (Not on my ding a ling). It is only noticable if the skin is strecthed. When i sweat it itches and my underwear becomes hella-uncomfortable. I went to the doctor and he told me it was a fungal infection. (folliculitis) He then put me on some type of antibotics. Since then the big ol bumps have receeded, but the white hair follicles remain! He said that people are built differently and it is due to friction, sweat, and the bacterial make-up of your body!!! Still see your doctor to be safe!!