look at my arm

for some dodgy reason i always get a bruise on my left arm when i give blood

Never bruised me. I just hate ripping me hairs out getting the tape off. Not sure if one of the nurses told me to apply good pressure when they first take the needle out and you hold the dressing as it prevents bruising.

i never get one on my right

I've tried both arms and prefare it in my left arm.
Strange how it can be completely different experience if they take it from the other arm.