How do you tell the difference between the drug working and just a good week?

Is a baseline blood test really necessary before starting something like this?

Stupid question: how do you know whether what is in the vial matches the label at all?

Is a baseline blood test really necessary before starting something like this?

Following this because I am in the same place and have no idea what to ask at the appointment.

Sorry for the basic question, but how do you actually start one of these diaries?