Scott Adams (creator of the Dilbert cartoon) has some wise counsel on discerning what you’re good at:
In summary, the two opinions about your abilities that you should never trust are your own opinions, and the majority’s opinions. But if a handful of people who have a good track record of identifying talent think you have something, you just might.
You can read the whole post here.
As it applies to Christians discerning calling, it’s important to remember that our callings (whether to marriage, to a job, in a new life direction) should not discerned by the individual alone (autonomy) or everyone (democracy) but rather by good counselors (a trusted community).