Being a Christian is having faith in Jesus Christ, and trusting HIS sacrifice at the cross to cover your sins. You have to born again and have the Holy Spirit. It really comes down to faith and doing HIS will.
Well, in my opinion, every one will only know on Judgement Day, but that would be debatable with many believers. Hope this answer's you question. Keep trusting! Whenever you have any doubt, trouble, fear, joy, or anything, pray about it. Losing communication with God is what happened after Adam and Eve ate of the fruit, Jesus opened up the direct communication. Don't ever be afraid to pray.
Keep reading your Bible, fellowshipping with other believers, pray, trust in Jesus, and seek HIS will. These seem like essential building blocks.
Bible verses for clarity.....
Romans 10:9 King James Version (KJV)
9 That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.
Luke 6:46 King James Version (KJV)
46 And why call ye me, Lord, Lord, and do not the things which I say?
Matthew 7:21-23 King James Version (KJV)
21 Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
22 Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works?
23 And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.
Revelation 14:12
Here is the patience of the saints; here are those who keep the commandments of God and the faith of Jesus.