Thank you for your patience. There a few things that could be happening here with your girl over the last few days and tonight, and from what you have said, it is more likely she coughed up the clear mucus rather than vomiting it up. If the coughing is becoming more regular, then we have to consider whether this could be from irritation from pulling on the leash, or whether there is a primary lung issue here like infectious canine cough (aka canine influenza). If she has been in contact with other dogs, we definitely need to consider this, and this typically causes a 'goose honk' type of cough. If this seems to be the case with your girl, then getting her seen by your local vet first thing tomorrow morning would be a good idea. If she pulls on the leash, then this cough could be from irritation to the trachea. As such - you should try her with a 'halti' to see if she will stop pulling and train her to heel, otherwise, you could try her with a harness instead of a collar if she doesn't already have one.
If you think she definitely vomiting tonight rather than coughed, then she is likely still nauseous right now and as such, you may want to try her with a little pepcid. The typical dose for this type of situation is 0.25mg per pound of body weight up to twice daily. You can read more about the use of Pepcid in dogs online here: http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid
Hopefully she is otherwise ok at the moment. For now, please keep an eye on her mucus membranes, capillary refill time and respiratory rate tonight as follows (do be careful that your girl doesn't try to bite you):
Mucus membranes - flip her lip and look at the color of her gums. They should maintain a nice salmon pink color. Get her 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 her 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 she seems to be panting or breathing rapidly throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
Best of luck with your girl and if this coughing/breathing issue continues tonight, please do get her seen first thing tomorrow morning. 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!
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