Hi afdebbas,
From what you've described, there are a couple of 'issues' here.
First, you assume that you were rejected from these Schools solely because of your GMAT score and that is likely NOT the case. With highly competitive Schools/Programs, you need to have a strong OVERALL application AND you have to present yourself correctly. You might have been a great candidate, but you messed up something on your application. It might also be that there are other parts of your application (essays, Work Experience, interview) that didn't actually help you to impress the Admissions Committees.
If you have not yet done so, then you might find it worthwhile to work with an Admissions Expert on your applications. There's a Forum full of them here:
ask-admission-consultants-124/As far as your GMAT is concerned, with a Q43 you were likely pretty good at the straight-forward 'math' questions that you faced on Test Day, but you missed out on LOTS of 'strategy-based' points (especially on DS) and you would have made some silly mistakes throughout the section. To raise your Quant score, you're likely going to need to invest in some new 'non-book' resources and learn/practice some new Tactics.
1) Have you scheduled another GMAT appointment yet?
GMAT assassins aren't born, they're made,
Rich