Piano practice struggles

[adomiscz]

I am a classical piano student, I have my conservatory entry exam in 1 month and I have a serious problem. I had a year to prepare for this exam, but i was so lazy and didn't practice as much as i should, so most of the required pieces are incomplete and also my scales and arpeggios aren't on really high level. But here's the thing - it is still not impossible to learn all this and pass the exam, last week I was practicing 4-6 hours a day and had no problem with that. But last 3 days, my motivation is completely ruined, I dont know why, I really want to pass this exam, but once i sit to the piano, I just can't play. I can't play scales for more than 30 minutes, I am REALLY upset and depressed, I dont know what to do. I know it's my fault for not preparing earlier, but it is still possible to pass, if i just practice...