Discipline priest arena guide?

Hey guys,

started playing on Warmane recently. Before that I mostly played TBC. My main is a discipline priest, I played bunch of battlegrounds and did some duels but I've never played arenas before. Looking to start playing it and am curious if there is some guide on discipline priest in arenas. From what I've seen priests are very often focused the most and whenever that happens in an arena i get stomped really fast, especially if my team isn't peeling and ofc as a healer I'm the one being blamed. Would really appreciate any advice, suggestions, rotation, what to do when, what to save trinket for, literally any tips and tricks would be helpful, and also useful arena addons. Would love to find an addon that lets me know when warrior used pummel or rogue kick. I got InterruptBar but maybe I'm just not using it correctly cause it aint helpful lol

Also being focused by a warrior and a DK in an arena is such a pain in the ***, I'm having a really difficult time dealing with them and staying alive.

Thanks in advance!