Life is going to change, for the better! You've got this! Being scared is normal, it is a major surgery, and a major life change, I would think if you weren't nervous and scared to be out of the ordinary. I love that you already know you can do it! That's half the battle! As far as telling work colleagues...I never did. I am an intensely private person and I didn't tell but a handful of people that I knew would be supportive. I intentionally chose not to tell people who would be negative and work is just work to me, those individuals aren't allowed into my private life. However, it really depends on your comfort level and whom you trust with the knowledge and whom you choose to tell. Best wishes!