Yesterday and today I have been walking in a few fields of grain sorghum. Most of the ones I have visited have been heading out and flowering. The Sorghum Midge was the primary reason for the field visits but I found a few leaf-footed bugs and stink bugs along field borders and a good many head feeding caterpillars. These caterpillars were primarily corn earworms and tobacco budworms. The picture above is from one of the fields where I was finding them pretty regular with the worms ranging from two to five days old based on size. The picture below is of a corn earworm moth laying eggs in one of the fields I visited this morning.
Here is a page from the 2013 Georgia Pest Management Handbook regarding Grain sorghum pests. If you have any questions please feel free to call you local county extension agent.