So I've been studying for a few weeks and the last 5 practice tests I've taken I've scored in the 710-750 range, with 760 on my first GMATPrep test. However, I keep thinking I'm getting "lucky" on these. My quant score has improved from around Q41 to Q47 with one Q50, but I really don't know what concepts I've grasped. It seems like for the questions I've gotten right, it came down to "thinking logically" and solving a problem. And I keep thinking if they changed it a certain way I wouldn't be sure I'd get it right.
This worries me because I feel like I can suddenly go from getting most of the questions right to getting most of them wrong. Anyone else feel this way? What to do when I see improvement but not sure how? My scores in both Q and V have been relatively consistent: Quant around 47, V around 44, but it each time I feel I "think-ed" my way out of a problems and didn't really grasp any fundamental concepts.