If they prepare the injections out of your sight, they should have labeled them. Not all MAs do. If you asked to see the vials medicine was drawn from, that would have eased your mind. And it would help if you stated what the injections were. The MA would definitely have told you. I agree though, you are not paranoid but you should know what questions to ask and ask that meds be prepared in front you should there be a 'next' time.