ouch! I've tried to shave my pubes with a razor like that before, and I learned my lesson really quick! I got nicked quite a few times, and ended up with razor burn/rash the next day. My suggestion would be to trim your pubes up with scissors, and for a closer shave (like to shave your balls, the base of your cock, or to go for the hairless look) use a fresh disposable razor or a razor like a gillette mach 3 or something like that, and some shave gel for sensitive skin, and shave WITH THE GRAIN, not against. hope this helps