Wow, I wasn't expecting things to be that severe for you. eek But at least you appear to have medicine to keep things under control. I pray you are quickly healed.
I can't remember if I mentioned this in previous comments, but I've been a regular donor since 2009, donating in the spring, the summer, and the fall. (I have to take the winter off because I choose a double-red-cell donation that time and there has to be a minimum of 16 weeks before donating blood again, thereby bypassing the whole winter season.) That being said, I'm well aware of the procedures and risks used, and I've got it down to a science: I wear a watch and start timing from the moment I start squeezing my hand to get the blood flowing. Depending on how well the nurse stuck the needle in my vein, I can usually fill the one-pint donation in about ten minutes. Afterward, I slowly sit up and rest for at least five minutes before climbing off the bench and leaving the room. (I made that mistake one time in my early years, getting up way too soon after the fact and quickly becoming light-headed.)