You have a burning desire to become a famous big name preacher with everyone clamoring to have you come preach in their church.  This must surely be the call of God. 

The call to the ministry is never a call to self-exaltation.  It is a call to give up all and follow Christ.  Jesus said that the one who wants to be great should learn to become the servant of all

You have studied all the doctrines and are an expert on any theological subject.  You can preach on any subject at the drop of a hat.  You must be called to the ministry. 

It is good to have knowledge that can be used for the Lord, but it is not essential to the work of the ministry.  Your knowledge might help if you have a call, but it will not qualify you to be called.

You have failed at everything else you have tried in life, so surely it stands to reason that you must be called.  The Lord has caused you to fail at everything so that you would go into the ministry. 

If you have failed at everything else then you will most certainly also fail in the ministry.  The work of the ministry requires a commitment and determination far greater than any other work.  It will bring far greater pressures than you have ever known before.

You have a natural ability to instruct others and  people are often coming to you for advice.  Surely a person with such natural talent must be called to the ministry. 

The  call of God imparts abilities you did not have before.  If your ministry was based on your natural talents then you would not need the Lord's help.  Your calling comes from God alone and makes you totally dependent on Him

Your have a great power in oratory and debate and always win your arguments.  You are perfectly qualified to be a preacher and to convince people from the Scriptures. 

The same thing applies as the previous point.  Although your abilities can be used by God if you submit them to Him, He doesn't need them to do His work.

You are a strong natural leader and people look up to you and respect you.  This obviously makes you a perfect candidate for the ministry. 

Leadership in God's Kingdom is based on submission and letting the Lord rule through you.  Your natural abilities might just get in the way.  As in the others, the Lord can use these abilities but He does not need them.  The Scripture says that God has chosen the weak and foolish things to confound the wise. 

1 Corinthians 1:27-29 

27 But God has chosen the foolish things of the world to confound the wise; and God has chosen the weak things of the world to confound the things that are mighty; 
28 And insignificant things of the world, and things that are despised, God has chosen, [yes], and things that are not, to bring to nothing things that are: 
29 That no flesh should boast in his presence.

You are highly educated and above average intelligence.  With your ability to study and absorb knowledge you are able to understand the Bible better and teach it in detail to others.  

Knowledge of God's Word does not come by intellectual study but by revelation from the Holy Spirit.  No doubt you would make a good elder in the church, but a teaching ministry is a gift from God, not a natural ability.

You have a degree in psychology and are able to counsel anyone with problems. So you would make a great shepherd and counselor. 

Actually since most of the psychological views are based on the reasoning of man and not the Word of God, your knowledge will be more of a hindrance to ministry than an asset.