Well I braved it again - and gave blood tonight for the second time!
After an hours wait, I was eventually called through and had my iron levels tested. Another 20 minutes wait followed before I was taken to the relaxing seats. The very, very young nurse tried to locate a vein on my left arm and then decided to change to my right. I became slightly apprehensive when I was told my veins were very thin and the young nurse had to ask a colleague for advice on which vein to go for! However, I need not have worried she didn't hurt me at all and I was soon enjoying a cup of coffee and bourbon biscuits!
All in all not a bad experience - even with the long wait - a good excuse to sit in peace and quiet with my book people watching!