I had it done in HS also. And that was the first and last time I had I had such an experience. The person doing it pricked me tons till they found a vein. I was crying cuz it was painful. In the end they had the other person do it and he got in one shot. It’s just 3-4 vials I think and they are small.
Ps I have small veins but had quite a few blood draws both before and after dy that had no problems but dy was def the worst experience I had for a blood test. I would say 95% of ppl dont have a problem so based on that you will be fine
Also drink extra water before and if you can have some water/oj after so you don’t feel weak
Hatzlocha. You’ll be fine