Hello and thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 25 years experience and would be happy work with you.
It may be that the lamb upset her GI tract and her vomiting and softer stool are due to that. It can take a few days for her stomach to settle down. I am a lot less worried since she had an exam yesterday and you have medication that you are giving her. Her having a good appetite still is also a good sign.
While her gut is settling down, it would be a good idea to fast her for at least 12 hours. Since she is an adult dog, a 12 hr fast will not hurt her. Continue to offer small amounts of water at a time. When you do begin feeding her again, you will want to offer frequent, small meals of the royal canin diet. If the vomiting and the stools improve, I would continue that for a few days and then slowly wean her back onto her normal food and feeding schedule. If she continues to vomit however, I would let your vet know and they may want to prescribe a different medication or follow up with abdominal xrays.
I hope this is helpful. Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please reply so I can clarify for you.
My posted replies are for general education only and not meant as a diagnosis. Only after a thorough veterinary examination can a diagnosis for your pet be made and specific treatments be advised or medications be prescribed.