Yep. kill it start from square 1. This is usually why I start 3 new plants when 3 others are 1/2 vegged. So if I do catch a male I kill it and get work on the next plant.
Yeah, I have three others about the same size, but they're all from seed and haven't sexed yet. This one was the first. I would be happy with two nice sized ladies. Just crossing my fingers that the others don't turn male too.