hi anin,
Sorry to hear that. I think you've come to the brutal realization that doing an endless supply of questions is not going to help you do well.
You can do thousands of practice questions and still get the same result. Remember the definition of insanity? --Doing the same thing you've been doing an expecting a different result each time.
What you need to do is change the way you are thinking. You need a thought process that is accurate enough to be correct, yet quick enough that you'll finish the exam without worrying about timing.
Don't judge your progress by whatever books you used. Sure, books can be helpful, but what you need to change is your thought process! So give a break on the books and learn from someone who can show you how to think efficiently! Hopefully you can find one fast so you can get back to your social life--which is important too!