First orange is a definite indicator of male in season. Although some males will then stay and orange color. On rare occassions a female will develop the orange color but on them it is permanent. We have had one female in out rescue that turned orange and stayed orange. We had always assumed it was a female and when she laid her eggs (while orange) we had no more doubts.
The femoral pores at that age in a male might not be prominent yet. They do have slightly different ages in maturing depending on health, habitat etc. As far as the pooping in the cage. Many males will do this when in season even some females will start pooping in odd places. If you are patient and calm he should eventually calm down. At that age it seems to be more like puberty than actual breeding season and will "usually" not last too long. Please don't take that as a definite rule because behavior can differ between one iguana and another.
As far as getting him to go outside again, if you notice him starting to go in his cage hurry and take him outside. If he makes a mess clean it immediately so he doesn't associate it with a new "bathroom". Also if worried about the carpet, if you don't already have a tub in his cage this might be a good idea. A clear flatter storage tote from Walmart or another store placed in the bottom of his cage with water in it will sometimes become a temporary if not permanent bathroom. The instead of cleaning the carpet you only have his tub to clean out.
Stephanie
IIRBS