I've always used Banamine injectable, but never injected it. I draw it up in a syringe too (and Chanda's dosage is correct) and then take off the needle and squirt in the mouth. With all the mucous membranes in the mouth, it goes to work VERY fast. But she's right, it tastes awful. My vet preferred to use it that way, and told me about vet students when he went to school that used to take it orally themselves instead of ibuprofen or other pain relievers! Goodness!
I'm sure everything is so new to her and she's over-doing a bit, as Chanda said. But, as she gains strength with you, I'm praying for a great turn around for her!
Again, thank you for saving this wonderful little "gem".