Hello and welcome to HCM,
Blood drawing with a needle stick is sometimes associated with pain and formation of purplish ring around the site of puncture.
This is more often when the needle stick is disturbed from its position.
The disturbance of the needle leads to tissue injury
and extravasation of the red blood cells in the tissue and thus the bruising.
There is nothing to worry about it.
will clear away within few days.
You can take some pain killer for the pain.
Thanks and take care
Dr Shailja P Wahal