Major writer's block: looking for suggestions

[billiepw, CNA]

I'm applying for UMass Boston ABSN and it's possible that it's just the way that CommonApp has formatted their site, but it's thrown me off a little.  

I understand that we need to submit a 500-word essay about "what is professional nursing?"  Fine.  But, click on Documents (which is how we submit the essay) and it says "Personal Statement" and gives the option to submit.

So, am I to submit an essay or a personal statement or both?  And if both, I'm not sure I know what that looks like.  Maybe I've been looking at this for too long.