Nervous about leadership?

But the Lord said to Samuel, "Do not look on his appearance or on the height of his stature, because I have rejected him. For the Lord sees not as man sees: man looks on the outward appearance, but the Lord looks on the heart." (1 Samuel 16:7 ESV)

Be encouraged by this. David was the unlikely candidate. Think of Timothy also. God uses people of all shapes and sizes. Look at Titus 1, even the qualifications for an elder (which implies someone who is old) does not include an age guideline. Don't limit what God can use you for because you are nervous about what-ifs. Moses was terrible speaker and became a mouthpiece for God. Strive for excellence, equip yourself with truth and be ready anything. God will appoint you when you are ready. Your role is to be prepared to trust him.