Hi:
I 'm a nubie here, but yes I have felt called at time to G-ds work for him, in small ways, and have felt his lovin grace within me. As far as not finishing a job that G-d wanted me to do, I've felt that I have either finished it, or he stopped me till a later date to fulfill a mission that he wants done.
I've always looked for signs of what G-d has for me, and keep a close ear for my Guardian Angles words or instructions