Yes, i too now have trouble and its been about 12 mnths.I ask them to get the blood nurse now.They seem to find a vein straight away without any pain or drama.Ive been told to drink a lot of water before hand,makes it easier for them to find.Also if they soak your arm in a bucket of warm water before hand.
I too have had lymph nodes taken out so only have one arm that they can go from.It must of been an ordeal for you.It wont help for next time as you will be tense to start with.Talk to tham when you get there and discuss the problem before they try again.
Goodluck next week let me know how you got along.
Take care
Annie x