normal and worthy, you should be thinking about it. Anxious, no, that is not the primary feeling that should be at work hear, anticipation, desire, but not fear. Continue whatever preparation your parish and diocese have prescribed, and spend most of your free time between now and Confirmation in prayer. The novena to the Holy Spirit, the traditional preparation for Pentecost, is the ideal prayer. So is meditation with scripture about the Holy Spirit–a list of these has probably been provided to you at some point. Journalling about your reaction to these scriptures, and about your feelings is also valuable. In this diocese candidates are expected to write a letter to the bishop asking the Church for this sacrament. This is a good practice, at least for your journal, so you do get these thoughts in order.
What do you think is required to be “ready” for Confirmation? If the bishop has called you, and you have done your best to prepare as required in your parish, and you want the Holy Spirit to come to anoint you and bestow his gifts, you are ready.
The other choice you have is to reject the sacrament, reject all that it stands for, and reject your commitment to the Catholic Faith. If “I am not ready” really means “I do not accept the responsibilities of an adult Catholic” yes, you do need some help, especially pastoral counselling from your priest. If it means, “sometimes I have doubts but I want to believe” or “I don’t feel worthy, holy, mature, wise” those are actually healthy feelings, we are not worthy, it is the Holy Spirit who makes us worthy.
Intense study of the faith as we undertake at this time inevitable raises questions, that is the purpose of the study. Ask those questions and take pains to resolve them, and acknowledge that in many areas your human knowledge and ability to understand is necessarily limited. That is precisely why we desire the gifts of the Holy Spirit, so he can bring us to knowledge and understanding.