A lost cause?

[crimson-queen.livejournal.com]

You guys may remember that I posted the princess peach dress I made for halloween this year. That was my first sewing project and since it came out pretty good I decided to try to make a holiday dress that I can wear to Christmas parties I'll be going to this year. I bought really pretty silver, white and black plaid fabric and got to work. I'm usually a size 14 so I cut my pattern and all my fabric. Problem is, the sleeves are too small (the rest of it may be too but the arms are the only thing I've been able to try on so far). Is there any way to salvage it without starting all over or am i screwed? I'm really not very good at this so I'm at a complete loss and ready to just scrap the whole project.