Thank you for your patience. There are a few things that could be happening here with your Chihuahua mix girl to cause this sort of distress and panic, followed by grass eating. Her grass eating behavior is certainly a sign your girl could be nauseous, and it could well be that she has managed to eat the fly which has in turn caused this behavior from her, or that she is having an allergic reaction to something. Hopefully she has calmed down now, and if so, get her to have a good drink of fresh water and keep an eye on her for the next 30 minutes or so.
Because she is likely nauseous, you may also 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 . For the next half hour or so, please keep an eye on her mucus membranes, capillary refill time and respiratory rate 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 hopefully she settles down soon. If you are keeping an eye on her and she seems to become more distressed, or if she develops hives or any local soft tissue swellings, then this is a sign of a potential allergic reaction due to bee/bug bite or sting, and would be cause to visit your local ER vet. 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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