It started about 3 weeks ago with a tiny white bump on the shaft of my penis that looked like an ingrown hair, I popped it once, and white pus came out of it, not a lot, and it was still there, I popped it again about 2 days ago and then a bigger bump appered, and is slightly red but is about 3 mm long and 1 mm wide, it goes across horizontally across the left side of my penis, maybe it's a zit coming in but I'm not sure, can someone please help?