Birmingham skipper Carsley was sent off after 36 minutes of the Blues' 2-0 victory over Wanderers for a high challenge on the Scotland international.
But Iwelumo will have to wait until the inflammation on his right knee settles before he can undergo a scan to assess the extent of the injury.
He told the club's official website: "I've looked at the challenge and I turned my back to it and bent my leg which Steve Kemp [Wolves head of medical] was quite happy about.
"It's throbbing a bit at the moment and I've got a brace on it so I can't move it at all. I knew it [the tackle] was coming but it was just one of those things that are part and parcel of football.
"Lee came in and apologised afterwards. It's not part of his game and I have to take it on the chin - you know you're going to get knocks here and there. Me and him [Carsley] have always had a bit of banter together on the pitch so I don't think there was any malice in it."
"I'm now looking at a worst-case scenario of eight weeks out with a torn cartilage - best-case scenario would be 10 days."