I donated blood for the first time about a year ago. Fortunately, everything went well. I didn't have a bad reaction or anything. So naturally, when I went to donate again recently I assumed everything would go okay this time too. But people can and do have negative reactions. It isn't a big deal though but it can be very unpleasant and even a little scary. I've worked in the medical field so I knew these reactions could happen and I wasn't too freaked out when it happened to me. I was a little surprised though. I thought I had done everything that they tell you to do beforehand to prevent it.    Everything started out fine. I don't have an issue with needles or anything like that and the entire process takes about 15 or 20 minutes so just played on my phone the entire time. It wasn't they were almost done taking the full amount of blood they needed that I started feeling bad. At that point, I told the staff what was going on. I started feeling very lightheaded. Then I felt nauseated and…