GFE means a more intimate experience, with LFK/DFK, DATY, BBBJ included.  

PSE is generally a wilder, more active experience. Think DT and gagging, CIM and COF, acrobatic hard sex, often greek included.  

It's attitude and how you do what you do that seems the biggest difference to me.  

When you say "everything unprotected", I cringe. As I said, uncovered oral is probably expected in most cases, but BBFS or BB Greek is probably neither expected nor offered (I hope not).  

I'm sure you'll hear other opinions on this. You can also use the search function on this and some of the other boards... this is a topic that comes up often and there are many threads that address the question very well.

Girlfriend Experience - GFE is basically doing with a client what you woukd do with your boyfriend if you had only been with him a short time so far.  Have protected sex, flirt.  Be human.  Talk, cuddle. Make sure he and you are having a good time.  DATY and BBBJ is usually on the menu for GFE but NEVER BBFS!!!  That is just irresponsible for both parties.
Porn Star Experience - PSE is basically what it sounds like.  Non stop sex, sometimes in crazy configurations.  Trying to make him cum as often as possible perhaps including anal, rimming, bondage, or any combo you might have seen in a porno.  Its generally debauchery at its finest.  Its less about you and more about him.  It includes all of GFE plus MORE!  Most guy's perfect GFE date would include shades of PSE.  Also, no BBFS.  Its dumb and dangerous.  You set the rules.  No one else.  Be safe and be well.  Most of all have fun and make money!  ;

So I'll just reiterate a couple of points:
1) There is never, ever a legitimate expect ion of BBFS, only BBBJ for GFE.
2) While some may disagree, PSE often includes Greek and a higher charge for Greek is not uncommon
Good luck, May!

GFE is supposed to the sex we all like to have...which is with ladies that are attractive to us (i.e., hot) that is passionate and with mutual enjoyment by both parties.  This may lead to subsequent meetings, and who knows what from there  

PSE is where things are a bit more.  Where that goes is as far as the partners are comfortable with.

BBBJ is expected at both levels.  Protection is expected for FS or Greek (if you have that as an option). no matter what.