Hello Minn and welcome.
If you are scared, just seat yourself to the back and the outside. That will keep you out of the crowd.
BUT if you are a good swimmer... and you know you are faster than most of the people who are racing (look at last year's results)... then get yourself to the front. Having to swim around slower people can be annoying.
Also, typically in a sprint... most of the people there are not out there to win AG spots, etc. So they aren't as aggressive as you might have heard of.
Typically in sprints, after the first 100 yards it thins out and you don't really have to worry about anyone.
I have found too that if anyone touches your toes, start kicking really HARD. They back off immediately. That let's them know you are there and that you aren't playing. They will get kicked. I have never had anyone continue to move on me after I let loose a serious kick on them.
Go out there and have fun. Trust me, if you are a strong and fast swimmer you won't have anything to worry about.
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather, to skid in broadside thoroughly used-up, totally worn out, and loudly proclaiming: WOW WHAT A RIDE!!!!"