For the blood tests, they just do one needle and use lots of vials ITMS. When they have enough blood for each test they remove the vial and replace it with a new one. The only difference is the GTT as they need to take blood at the start then after one hour then after the second hour.

So yes - you can get them all at the same time.

HTH

ETA They like to have an appt for the GTT. Usually they will make it for the morning as you need to fast.