So I'm new here and I just need to vent!

I have been doing my masters write up for over a year now, every time my submission date approached my supervisor extended it by at least two months (original submission date was 28th february 2011). My supervisor is always super busy and waits until last minute to look at my work and give me feedback....well until august when he was told we cant extend it anymore! And i was finally so happy that because he now gave me full attention because no matter what I have to submit the thesis by the end of this month....just yesterday I am told I used the wrong data analysis for my work and I have to analyse my data again.

Now I dont know whether to laugh or cry. First of all I am a layman in stats, I struggled to get my data analysis done. My supervisor has seen it numerous times, we even did some of it together, and im told its wrong now?? I have been given this test that I have to do instead and its my first time hearing it. Im looking at the program I have to use in SAS but it makes no sense to me. I only have until the 31st of this month to get everything done...I dont think I can master this new analysis, do it, and re-write my results and discussion chapters in the space that's left. I am exhausted already from all the extensions I've had, i havent been able to do anything else all year because of my write up....I was going to hand in my last draft (a perfect one) on monday.

I DONT KNOW WHAT TO DO!!!! I feel like in the end, I've failed :-(

What are my options? do I have any at all??

Thanks!