Yeast infections & implants?

I'm 15 years old. A week ago yesterday I had my implant fitted the second time. Not long ago I decided to be natural and keep the periods & girly mood swings and get rid of the implant but as I've had so many pregnancy scares, I decided to get it back in. It's been in my arm for a week now, but the problem is, I also keep getting yeast infections? Why is this? I have anti fungal cream to cure the itching and pain down below, but nothing seems to cure it completely, so far having the implant out I kept getting infections, my boyfriend is clean & is definitely STD free. 
I clean myself every single day, make sure it's all very clean down below. At the moment I'm suffering with a infection, which I assume is thrush again, clinic isn't open til Monday, but whatever they give me doesn't seem to cure it for good..:( 
Any advise or similar stories?