Sounds like a growing roo to me. Do your others have tails yet. If he doesn't have one, and the others do ; he's probably a roo.
A roo CAN be too big if all his hens are a lot smaller. Not only will he be rough on them when breeding, but his sheer size, and sometimes resultant clumsiness, may impair fertility.
I was worried about the size. He is total cuteness though. Of the 12, five have tail feathers and body length wing feathers. The others are a bit larger in size and have no interest in feathering out. I was suspicious that I ended up with 5 hens and 7 roos!...oh my... No worries though. My goal/dream/hope was to have 4 hens and to have a rooster and a spare.
Thank you for helping.
If someone has time, one more question. Given the Orp size, how many could I comfortably house in a 4 x 8 coop?