b12 will help all the time. Suspension, again as B-boy said, can leave some pretty nasty lumps so you want to be careful so close to the show. As for the last shot on thurs, if you do not get any lumps or localized swelling then sure. If you do then it will depend on how quickly your body deals with this that will determine when you shoot the last one. I have not really had any issues with test leaving lumps, so I have in the past run prop the day before with no probs, fine if you can get away with it.