what is this spot and how do I get rid of It?

I have noticed a spot the size of a pea right at the top of my lady garden making any sexual act impossible due to the pain. It is painful to wear my usual pair of jeans as they are too tight and rub. Is there any cream I can get for it ? What do I do ? I get it all the time usually after my cycle but never has it been this bad. Please help, thank you.