First Commerical Pattern

I cut out my first pattern last night and I sewed all night in my sleep. The next day, I pinned the top together to try it on and it is huge......doesn't fit at all.......I mean I could go camping in it.........


I checked the pattern and it is one of those multi-sized patterns and I didn't want to ruin the pattern so I cut on the largest size.........hmmmm not sure what to do........I really hate to ruin my pattern by cutting off a couple of sizes. What if I pick the wrong size and what if my body doesn't match the patterns sizes?

And since life isn't fair, my upper body is a couple of sizes smaller than my lower body.  I think I'm a pear shape.  And I don't really match the sizes on the back of the envelope.  What to do?