This makes my blood boil and why I'm interested in looking into patient advocacy.
First of all, prepare a document so it's down in writing. Copy and paste your post here and edit accordingly.
You need to then get that document into the hands of the layers of management above the minions you've been speaking to. All of the layers to the top. Find out the names of the head of surgery, the head of surgical nursing, all the appropriate bosses all the way to the top.
The minions are used to people telling them they're scared of needles so they are programmed by this to downplay your very real issue. Do you have a friendly outside doctor who can intervene for you? Your GP? A psychologist? Your breast surgeon? Maybe your breast care nurse if she's a good 'un?
Demand a reason (also in writing). Why won't the do it? Ask for this reason to be provided in writing. Say it may be needed in a compensation claim for unecessary trauma after the operation.
You're going to have to spend the next week being a complete pain in the arse to them. But the squeaky wheel gets the oil.
Lodge a formal complaint if no one listens.
If you get no joy, contact the local paper about the heartless treatment you're receiving. Show them the pucture of your Clexane bruised stomach. Tell the hospital you're doing this.
@Zoffiel may be able to help with this 'problem'. Let us know how you get on. K xox