Because the Holy Spirit is God, we feel Him as He controls our circumstances and transforms our lives. When He does that, He uses us. He melts us in relationships. He molds us in the pursuit and the direction of His will. He fills us with power and the perseverance to keep at it. He uses as He controls our circumstances and transforms our lives. Ask the Spirit of God to use you, just as you are, with the gifts and abilities that He's given you. Secure in the confidence that God is in control of your life, you will be free to serve Him with joy and effectiveness.
There are times when you're tired and times when you don't believe in yourself. That's when you have to stick it out and draw on the confidence that you have deep down beneath all the doubts and worries.