Score is going down rather than up...

i took the GMAT the first time two years ago and got a 680 (47Q, 37V). I retook it earlier this year and got a 690 (42Q, 42V). I decided to retake it as I wanted a 700+. I had my old GMATPrep exams and MGMAT exams, from a while ago and for the past 3 GMATPrep and 2 MGMAT tests i kept getting anywhere from the 710-730 range.

I took it again and got a 650 (43Q, 38V) - I cancelled it.

Has anyone ever experienced this?!?!? This is super frustrating as my score looks as though it's tanking and my highest official score has a horrible quant score.