I'm sorry that you're in this position.
There is no easy answer. You could reapply this next cycle, and hope you get a spot this time. Unclear what you can do between now and the next cycle to improve your application. If you have a home surgery program you should contact them and ask for honest feedback. Explanations like "it was a competitive year" won't help you -- sure, it was competitive. But why was I less competitive than others? You may not like the answer, but you need to hear it.
After a full EM residency it's possible you might bring something "new to the table". But would depend upon which EM residency you are in (big acadmic center would be better). It might allow you to work with surgeons at your EM program and get into a GS spot there.
If you try to reapply next year, you'll need to hope that your EM program is willing to support you.
But you will also run into a funding issue. Now that you're in EM you get 3 full years of funding. Even if you switch to GS after a single year, you won't have full funding for your entire GS training. Whether that's important to programs will vary.