I'm A 17 Year Old Female Who Realize After Using

I'm a 17 year old female who realize after using a cheap razor I started itching down there and it been going on for months now because I th I had a yeast infection and my healthcare doctor gave me medicine for a years infection and weeks later gave me medicine for a bacteria infection also itch cream but the cream doesn't help I also bought vagisil for the itch but that doesn't work it seems like Ive tried everything and it don't work I'm about to start school in a few weeks and I conti to itch down there and I don't know what to do