What can my mom do about seeing a different surgeon for follow up?

My mom recently had a plastic surgeon remove melanoma from her leg. He ended up doing a skin graft as well. Long story short she had quite a bit of excess blood covering her bandage and even in her boot. I told her to see if the office had a on-call surgeon where it was after hours. She ended up talking to the surgeon that did her surgery. All he did was yell at her and tell her everything she wasn’t doing that really she had been and continues to be doing. He didn’t believe her. Her post surgery appointment is in a couple of days and she really is not happy with him and would like to see a different doctor.