The new spirit God gave us is not one of fear...we have all that we need to walk in the Spirit - power, love, and self-discipline. Don't follow your heart, feelings and passions fluctuate and will cause you to become confused and stumble. Instead follow Jesus, who is constant and true, he will never cause you to stumble but instead will lead you to everlasting life.
"The human heart is the most deceitful of all things, and desperately wicked. Who really knows how bad it is? But I, the Lord, search all hearts and examine secret motives. I give all people their due rewards, according to what their actions deserve." Jeremiah 17:9-10