You might have a infection
Could be a yeast infection. There are over the counter meds that can alleviate your symptoms. If it's real bad, or the first time you've ever had this problem, it's good to go to the doctor to get checked out to make sure that it is only a yeast infection.
It could be a yeast infection or crabs
Hi it more than likely sounds like thrush which can be cured quite easily with cream or it could be pubic lice also easily cured with full marks solution.hope this helps.