you doubt that 6,000 years or so has past since creation...what makes you doubt this?
however as scripture interprets itself...many times in scripture a day is ...a day......or can even be an hour....or a year as in Daniel...but also has been shown to be 1,000 years...as in the day of the Lord....
the 7,000 year plan of God makes total sense in the story of Genesis and if one goes through the ages and dates of the Bible patriarchs....alost 6,000 years (6 days) of man's existence on this earth has gone by....with the last day...the 1,000 millenium rest day to come very soon,
What you may believe and cling to would be better shown with scripture and support therein.