Friend, the concern is that she may have part of the towel obstructed in the gastrointestinal tract as you already know. To determine if she does have a blockage she will need to have xrays with barium from family veterinarian. In the meantime, this is what you can do:
1- Do not give things like Pepto Bismol or imodium. You can start her on Pepcid AC (famotidine) 10mg every 12 hours. You can buy Pepcid AC over the counter in any pharmacy.
2- Hold the food and water for 3-4 hours to control the vomiting.
3- After 3-4 hours offer small amount of water, if no vomiting after 1/2 hour feed her a bland diet of rice (75%) and boiled boneless chicken or ground beef (25%). The idea is for the rice to help move any part of the towel out in the feces. Make sure you are checking her stool for the towel.
4- If at any point she becomes lethargic, anorexic, continues vomiting, constipated or diarrhea, etc. follow up immediately with ER veterinarian. These are all signs of a possible obstruction, otherwise follow up with family veterinarian for xrays with barium. It is best to treat her before she becomes clinically ill.
Please do not forget to rate my answer - I hope you found it to be excellent. If there’s more I can do, please use the reply tab and let me know. It’s my goal to provide you with excellent service." Thank you for your business and I hope to work with you again soon!