First appointment w/a personal trainer tonight and I'm SCARED..
A personal trainer should go at your pace. I'm sure he or she trains a lot of people that are very out of shape and have never been to a gym before. I mean, if you were in great shape and worked out at the gym all the time by yourself, what would you need to hire a trainer for? When you get there, just tell them you're nervous. They should start with an assessment where they evaluate your current fitness level and then develop a program that will meet your needs.
Please note: I AM NOT A DOCTOR. If you want medical advice, talk to your doctor. Whatever I post, there is probably some surgeon or other health care provider somewhere that disagrees with me. If you want to know what your surgeon thinks, then ask him or her. Check out my blog.