Do not give up !
Looking at your practice score, it's evident that u can make it !
... I believe it's two things that contributed, sadly, to your low performance.
First of all, had u get a lost of energy?
Not sleeping enough and a low stamina level are both the reason why, at the first, we cannot score as high as we can. To fight against this, u should do a GMAT test once a week with AWA sections. These tests should be done in the same conditions as the real one.
Secondly, were u nervous?
Here, it's always the same. We all think too much of the impacts if we do not score enough. We all imagine that we will never be admitted to our dreamt schools etc.... Well, it's easy here to say this but the GMAT is just a game in which no emotion has to be
... Our first enemy is ourselves
...But for what should we let this being real? Let explose your determination to kill this beast on the G day and during all your future preparation. God... That's not some questions on a computer that could defeat us !
... U will make it and it's the practice that will give the confidence.
Once in, I said myself "Well, I have prepared me for a while. I'm ready. I will make it now !"
... Weird/Hard questions have to tackle by strategies definied before the test. U should try to work on your 2 precedent attempts to build up some accurate strategies on how to tackle this test.
Good Luck ! :D