Did I commit the unforgivable sin - blasphemy against the Holy Spirit

Here is the settled pastoral answer: the very fact that you are worried about it is strong evidence you have not committed it. Jesus spoke of blasphemy against the Holy Ghost (Mark 3:28-29; Matthew 12:31-32) to Pharisees who were looking at his miracles and calling the Spirit's work satanic - a settled, hard, final rejection of God with eyes wide open, not a fearful believer's worst thought or worst season. Notice what surrounds the warning: 'All sins shall be forgiven unto the sons of men, and blasphemies wherewith soever they shall blaspheme' (Mark 3:28) - the doorway of mercy is deliberately built wide.

A hardened blasphemer does not lie awake grieved, wanting to be right with God; that grief IS the Spirit still working in you, and 'him that cometh to me I will in no wise cast out' (John 6:37) has no exception clause. 'Whosoever shall call upon the name of the Lord shall be saved' (Romans 10:13) - whosoever includes you, today. If this fear loops obsessively no matter how many times it is answered, see the entry on intrusive thoughts - that looping pattern is treatable, and getting help for it is wise.

But the theological question is closed: the person afraid of having committed this sin is the person who has not.