^^x2
I would hope you got some kind of dosage for this snake from a REPUTABLE (read "not the internet") source for the dosage of this antibiotic??
Did you also look up potential side affects and contraindications to the use of this drug in reptiles, and in snakes specifically??
Dosing animals with medication is not a task to be taken lightly…I hope you lucked out and managed not to kill your snake by doing this.
And CareCredit is a wonderful thing…there are homeless people who come into my Vet Clinic that can afford CareCredit
EDIT–and Injectable dosing of antibiotics can cause damage to liver and kidney as well, so don't think they will be less likely to cause damage if administered improperly….