Usually notice is one pay cycle, but not more than 2 weeks.

So if you are paid weekly, you could give one week's notice.

If you are paid monthly, you give 2 weeks notice.

I'm not sure what type of work you do. Do you have accumulated vacation time? Will you take it or take money for it? Take it now or at the end?

Let her be the dramatic one, that reflects on HER, not what you are doing, giving notice.