Writing to the church in Corinth, Paul said - "I came to you in weakness - timid and trembling" (1 Corinthians 2:3). Even Paul, apparently, had times of self-doubt. It’s a season of life, which we will all face at one time, or another.
Later on, Paul tells Timothy how he faces such times - "For God did not give us a spirit of timidity, but a spirit of power, of love and of self-discipline." (2 Timothy 1:7)
We can listen to our doubts, try to ignore or contradict our doubts or respond to our doubts in a faithful and helpful way. Paul identifies some of our doubts and tells us how we can respond - we are influential > set an example we are inadequate > depend on God we are invaluable > use God’s gifts we are incomplete > grow