It occurs to me I must have had this happen. Just once during a blood donation the needle went in and it BURNED and hurt for days afterward so they tried the other elbow. I remember seeing a big dark patch on my elbow more than once after donating blood. Ssh, don't tell my husband, or I'll never persuade him to start donating.... why won't he.... why..... it's roughly 90 minutes, start to finish.

Of course, I still haven't donated platelets (plasma?) because it takes two hours and the separate the yellow stuff and return the red stuff into your own veins, and somehow that (plus, TWO HOURS) just has me saying no, even though the need is great and I qualify to donate.