Hi luigi.roza,
Since your score goal is relatively modest, and you're so close to it right now, you have to think in terms of the work that you need to do to keep the little mistakes from happening. You don't need to correctly answer ANY question that you think is too hard or too weird, so you can 'dump' those questions. However, you need to correctly answer most of the 'gettable' questions - and right now you're missing out on some of those points. I'll bet that there are at least a few questions on every CAT that you COULD have gotten correct but didn't. If you do a bit more work on the PAD (NOT 'in your head'), take the proper notes, etc., then you should be able to pick up those missing points without too much trouble.
GMAT assassins aren't born, they're made,
Rich