There's a few things I want to address,
1. Feeling nervous or fear to act when God wants us to do something.
- First of all, we need to know it really come from God (wisdom and discernment, and a close walk with God).
- It's normal to feel nervous or scared. But here's the beauty of it, if we feel scared or inadequate, that's because we are, which compelled us to rely on the Holy Spirit (which is what God wants us to do).
- Find out why you're feeling scared. Is it the fear of rejection, the fear of man, etc.
2. Feeling of extreme anxiety when you didn't do it.
This is somewhat concerning. Because if it's from God, and say, we failed. God may reprimand or convict us, but He does so with love and will give us hope, not a feeling of dread or anxiety. Find out if this is really from God.
3. Rebuking others
This is very touchy and very tricky, need to approach with a lot of wisdom. We really need to be sure it's from God.
It's very easy to point out someone else's shortcomings. Sometimes it's very glaring, and a lot of times the enemy will point it out to us as well.
Are there times for rebukes, yes, but we really, really need to be sure it's from God and we need to ask God what we are to do with the information.
Here's a good article about rebukes.
When is it necessary to rebuke another believer? | GotQuestions.org
Do you have an accountability partner? Someone you can talk to and share about your Christian journey, struggles, etc., someone that can help you keep accountable?
And presently, do you submit to or is under any church leaders or leadership? Who will guide you in your ministry and also protect you as well.
Speaking as a friend/brother in Christ, if you felt that God wanted you to do something then felt extreme anxiety because you didn't do it ... I would really question if it came from God in the first place.
If you are in a church, find a leader that you can trust and look up to, talk to them about your issue and your desire to find your calling, make no mistake about it, you are called and there's a great calling in your life. But we need to be equipped for our calling.
I wish you the best in your calling, I know for certain God has called you and you have a purpose. Will pray that you will be sensitive to the leading of the Holy Spirit.
I'm trying to find out God's direction in my life as well, I feel like I'm in a 'transition' phase right now, so at the moment I'm just seeking His presence, find out what's next on my journey.