["I've started training people at work, which would have made me nervous a year or two ago.", "That's great because you really grew as a person.", 'Yeah I feel much stronger about my abilities now, and am ready for that task.']
Maybe later on you will be able to handle greater responsibilities.
I've started training people at work which I used to get real nervous about.  I feel like I'm experienced now though, and know what Im doing well enough.