GMAT Strategy

Hello,

I have exhausted my 6 MGMAT CATs online and have reset for a new set.
Just took a practice test this afternoon and had unfortunately many repeats (maybe 15% for both verbal and quant).

How accurate do you think is my score then ? I got 660 (Q45, V36). Do you think that my real level would be best reflected if I decreased my score by 15 to 20% ? I know that I don't "deserve" 660, on the other hand, I would really like to find a way to gauge my current level.

Thanks for any ideas !