Those are possible symptoms of vulvitis or a yeast infection, although you didn't mention any discharge.    From Wordnik.com.  [Yahoo! Answers: Latest Questions] Reference

The conclusions of a 1992 N-9 study were published in the journal JAMA 1992 July 22-29; 268 (4): 477-82 and stated that: "Genital ulcers and vulvitis occurred with increased frequency in nonoxynol 9 sponge users.    From Wordnik.com.  [ANC Today] Reference