Snakes will often yawn frequently before a shed, which can increase saliva production. That may be what you are noticing in your snake.
There are so many different treatment regimens with Baytril; my vet prefers weekly injections, I know many vets prefer more frequent injections or oral medication or a number of other things. Dosage and the severity of the RI also play a part in recovery time. In other words, it's nearly impossible to compare recovery times in different snakes.
For what it's worth, my vet gives my snakes weekly Baytril injections and I usually start to notice the most improvement early in the second week.
But I think this is really a conversation you should be having with your vet.