needle stick for blood donation hurt MUCH more than usual - why?!

Although I can't give you a perfect answer to this question, I can make some educated guesses.

1.The factory edge on the needle wasn't as sharp as it should have been. Dull needles hurt more than sharp ones.
2. There was a nerve ending near the point of entry for the needle. There aren't as many nerve endings in the arm surface as there are on the tip of a finger (and you know how much finger sticks hurt) but since it isn't something that is visible to the person inserting the needle, they might have inadvertently come too close to one.
3.Your pain tolerance was at a low point. Some days certain things just hurt more.
4. Phlebotomist error. Not enough traction (pulling) on your skin during the venipuncture, poor angle of entry, etc.
5. The antiseptic scrub wasn't dry. The stuff we clean your arm with is alcohol based and while we do have a drying period of 30 seconds that we wait before inserting the needle, sometimes that just isn't enough time. In certain light, an area may look dry even though it is still damp with the antiseptic. Alcohol + open wound = pain.
6. You moved during the needle insertion. What? It happens all the time. Even a slight change in the position of your arm can shift things around. Just because the technician apologized for causing you pain, does not mean they were the actual cause.

I can assure you that the technicians and phlebotomists who are taking your blood are doing their very best every day. Unfortunately, sometimes it hurts, sometimes bruises happen, and sometimes we can't get blood out of someone. This is the nature of phlebotomy. Thankfully, it usually doesn't hurt much, we fail on very few donors and many, many lives are saved by the blood we collect.

14+ years as a phlebotomist for a major blood center

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