Thank you for your patience. This sort of case is always of concern to be since so often I see young dogs, like Derby, in my clinic who have accidentally (or otherwise) ingested stockings, toys, bones and other objects when their owners weren't looking and more often than not, these need to be removed via surgery. Let's hope Derby is able to pass the stockings without an issue - thankfully they are soft and malleable, so will hopefully pass. It is also possible Derby managed to chew them and break them into small bits as well. As it has been 3 hours, it is too late to try and get Derby to vomit the stockings back up again, so you are going to need to keep a close eye on him over the next 2 - 3 days as they attempt to pass through his GI tract.
For now, please continue monitor his behavior, appetite and bowel movements over the next 24 hours. He should be fine in the short term, but to be sure please check his mucus membranes, capillary refill time and respiratory rate as follows:
Mucus membranes - flip his lip and look at the color of his gums. They should maintain a nice salmon pink color. Get his to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on his gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if he is continuously panting tonight, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
If he has any vomiting or ongoing lethargy tonight, seems painful or you are just overly worried about his state of health - get some peace of mind by getting him to your local emergency Vet clinic. It is always better to be safe than sorry.
There are a few things that could happen from here including anything from a partial chronic obstruction, or a full complete obstruction in his bowel, or even an intussusception where the bowel telescopes upon itself. It is also possible that Derby will just develop a gastroenteritis or that he could possibly even be absolutely fine! If Derby develops any symptoms of a potential obstruction (going off food, not passing a bowel movement, vomiting etc), then your Vet will want to give your boy some fluids, and take several radiographs (plain and contrast ones to help highlight a foreign body). If it seems as though there is something stuck in his gut, the next step will be an exploratory laparotomy (opening up his abdomen) or endoscopy to be able to get the foreign material out.
Best of luck with your boy, do continue to keep a close eye on him, and definitely get him seen if he develops any symptoms of a potential obstruction in the next few days. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
PS: If you have additional questions after you rate the question, you are welcome to request me for additional conversations if I am on-line or by beginning your question "Dr. E..." or "Pet-doc..." and others will leave the questions for me.