If you're converned about the needles, just don't look. There isn't very much pain involved, so from that end you should be fine.
I've never had an issue giving blood except for one time. When the needle went in and the bag got connected, the nurse (or whomever) walked away. She came back about 5 minutes later to see very little blood had gone into the bag. She adjusted the needle and told me to squeeze harder on the bag. It happened all at once, and I dumped my pint of blood in like 30 seconds. Then the conversation went something like this:
Nurse: "Are you ok?"
Me: "Yeah, why?"
Nurse: "Your face just went white, do you feel like you're going to pass out?"
Me: "No, I feel fiiiiiwwwoooooaaahhhh"
I didn't pass out completely, but it was pretty close. It was a very uncomfortable feeling. That being said, I give blood every time the blood drive comes to work, and I've been doing it for about 15 years. That has only happened once. Every other time... give blood, have juice and cookies, call it a day. I'm O neg which is universal donor. Who knows... it might be my own blood to save my ass one day. I wish more people would give. It's not like your body doesn't make more
I applaud your decision to give.