I'm glad your heart is healthy. It sounds like you are making good progress, so I encourage you to think positively about continued good progress in school and on the job. It's okay to be nervous at first on a new job, and it's okay to tell people you are. Many people are helpful to new comers and when they find out you want reassurance are happy to offer it. I wish you continued good health and a great work and school experience. It's hard but so worth it!