i had an infected bartholins cyst and had to have it surgically lanced (it surpassed the size of a golf ball within a couple of hours) - it was nasty. was inside the labia - not on the outside where leg meets labia - that sounds more like it may have been an infected sebaceous cyst (which i get semi regularly -but not that big - and they tend to pop on their own in an ewwwww fashion)

the scar for my bartholins cyst surgery is sorta alongside my clitoris to give you an idea of location