Extreme feminine itch, redness, yellow-white discharge, no scent?

Im 12 and i have extreme feminine itch, i wash everyday and apply vagisil itching cream but it doesnt help anymore. Its red around the hole and has a yellowish whiteish discharge. the itch so is intense i cant stop itching. what can i do? is there anything i can buy that can help in a matter of minutes? (i live in reno, NV) i tried vagisil cream and wipes but nothing is helping. I used to have a yeast infection, but it doesnt have a scent anymore. what is it and what should i do?? its so itchy its unbearable!!!!