I’m not surprised that you’re nervous, given the tiny size of your girl.
I’m far from an expert, but I didn’t think Propofol was normally used as the primary anesthesia during a surgical procedure. In my limited experience, it’s been used as a sort of pre-anesthetic, before the general anesthetic is given.
Here’s a brief article on canine anesthesia. However, you really should discuss your concerns with your vet. He or she should be able to explain the anesthesia choices being recommended and the reason for them. If the vet won’t do that ... I wouldn’t trust that vet.
https://www.whole-dog-journal.com/he...ary-procedure/