How do I explain this to my parents

I’m late to getting my license(I’m 29) and I was supposed to take my test this weekend but I felt I needed one last lesson to ensure I’m doing things correctly. I told my mom I was taking my test next weekend. After I get my license I’m moving to be with my fiancé in another state.

I went to book it and it was sold out. If I tell her it was sold out she’ll bitch and complain about how I don’t really want it and I don’t wanna move because it’ll be the end of February that I’m taking my test ect.

I honestly don’t want to deal with listening to her. I can’t not say anything because she’ll ask about having to take me for my test.