Its hard to tell you something, given the brief thoughts of yours. Remember: It’s your life. You don’t have to justify your choices - even if your mom thinks you had chosen badly. Being in your position, I would start asking questions instead of trying to prepare conversation scenarios that will likely not turn out in the way you’ve planned. And then listen, pose follow up questions and listen more/argue about the statements.

I hope that relieves your stress a bit. Have a great day!