Don't give up. My last semester I went into the final with a 77 avg., we had to maintain a 74. I made 73 on the final & graduated. Now that it is all over who cares what we made. I studied all the time too but sometimes it just didn't matter....
I have taken the PBDS twice & it sucks. The first time I was totally unprepared. The 2nd time I studied my butt off & still had "some weaknesses". You must watch the 2-3min. video clip of a pt. coughing, sweating, etc. & look at labs, ...