I had a lap nissen done about ten years ago and for the first time I am experiencing heartburn pretty often. I am also pre- barretts. Any advice?

EGD. It is not uncommon for gerd symptoms to return after lap nissen. There is no such thing as a "pre-barrett's". Either you have it or you don't. Its a endoscopic and histopathologic finding. I recommend you see a gastroenterologist and consider a repeat egd.
See GI doctor. Discuss this with your GI doctor. Since you had a procedure that cured your heartburn, and now it has returned, you need evaluation.