An IV doesn't hurt at all really. There is a bit of a prick when the doc or the nurse inserts the the needle into your arm, but as soon as its in your vein you don't feel it. Just try not to move it too much when it's in.
I get an IV every 28 days and its not awful. Personally, I would look while the needle is inserted. I only get a little anxious when I can't see the needle being inserted.