White skin around frenulum and foreskin, grateful for any answers?

There's a band of white skin around my foreskin, just under the glans, it goes right round to the frenulum, in one or two places, there are small white lumps, very small, and there's also a blister of some sort on the right side of my glans near the frenulum about half a centimetre or so long. It looks like it has liquid or something inside. Recently I've been putting on a cream used for athletes feet, and other fungal skin infections like Dhobi's Itch. The skin has gone darker a little, but it's still white, I am 17, but am too embarred to tell my nan who lives with me whose 63, 64. Help me guys please.