You have an elective that makes your "feel" hurt. I don't know what that is. Do you mean your "feet"?
Secondly, I haven't heard a reasonable answer as to why they should let you drop this. Quit moaning and complaining about this elective. Sit down at your desk and write down why you want to drop the class, if it's too late in the semester to drop it and what class you plan on filling with its absence.
When you approach your parents as a young adult, you are more likely to receive a more positive response to your request. You might keep that in mind.