Tired and Interview Jitters

I came home last night from my part-time job close to midnight knowing that I needed to get up by 7:00 am today for a telephone interview at 9:00 am. Since I don't work today, I had planned to spend the entire day preparing for an intense interview I have scheduled with another company on Monday. I was not prepared to be asked during the phone interview if I could come in later in the day for testing and an in-person interview. I'm feeling a little frazzled because my Excel test will be on the 2007 version and I have been using 2003. Huge differences between the two. I'm also taking a data entry test and let's just say I'm accurate, but not fast. Yikes! Also would be better if I'd had a little more sleep last night. But it is what it is and I'm attempting to calm myself and build confidence before I start getting ready.