What Causes Sores On Vagina ?

i have 3 or 4 sores on my vagina. 2 being around the opening. they never blistered or has puss filled area like herpes blisters are described as, they are just open and red. Last week before they appeared the area was extremely itchy. also last week i had underarm rashes, and i never have had a rash before in my life. there is also discharge and an odor. i have bean treating for a yeast infection with over the counter meds and it feels a little better today. what could this be?