thc levels in my body

I too would like to know the answer.  I got pulled over in my car and they thought I was under the influence.  They blood tested me and the blood test came in a 7.5.  I had not smoked at all that day but smoked at least 2 times a day for many days prior to that.  I am now being charged with an Operating While Intoxicated.   I have done a lot of research and have found numerous articles that state that the levels can remain high and fluctuate for many days after non-use.