They do use a local for a core biopsy. I had a fine biopsy for a cyst many years ago but can't remember how that was done. Try to leave it alone as others have said - there's no way you can self-diagnose and you'll only make things more tender. They do mammograms on anxious woman every day so just let them know that the area is tender, that the screening mammo hurt, and that you're very anxious. I was shaking so much at mine, I suspect I was being held up by the machine rather than my knees.
Ring someone up and make arrangements for a movie or a walk. It doesn't matter if you can't concentrate but you need to distract yourself. You've said that no-one can come with you but at the very least, if you can, make contact with someone who you can tell what is going on - it always helps if someone has your back.
