If you did the "wait and see", would it be harder to control than if you started the shots right away?

I would probably wait and see. Then I would probably end up giving the shots myself. After all, what are the odds that you would stick yourself AGAIN!?! Just be extra careful and DON'T give the shot if you don't feel absolutely comfortable (like if he is fussy extra bad that day). Try again later or the next day, even.