If you're getting scooped all the time you might want to work on survival and being dodgy. That's what stam NB is all about. Learn that dodge roll at the right times, gotta unlock that Vigor ability from PvP(It's a real game changer for stam) and a good option is the 2H "Rally" for insta-heals and heals over time with an added 20% damage boost.
PvP: If you're looking for the PvP aspect of stam NB, I highly suggest practicing rotations with immobilizing and stunning your targets with good timing in between each of their immunity timers to put stress on their stamina.
Impenetrable trait is also a large boon in PvP as it reduces a load of damage on your toon, although keep in mind that you still need to be fast and dodgy. As with any class and build, practice makes perfect; and remember, there's always going to be people out there better than you.
PvE: First basic rule of thumb is to have at least 20k health so you don't get one-shotted by mobs. (Vet levels). imo, I'd say if you're going for DPS, focus on killing the target faster than it kills you.Learn how to activate your passives in the right order; that's half the battle right there. Know your abilities before you make your rotations.
I hope this helps you start up a basic rotation and build on from there to create a terror of a stam NB in both PvE and PvP. Good luck out there, and good hunting. o7 ~Wolf