I don't get heartburn either but I do get a pain which is on my left and the doctor told me that this does happen sometimes. I also suffer with bad taste in my mouth and various throat problems. Once I started on the PPI there was a significant improvment and somedays I don't get any problems at all and others (like today) are not good, even though I watch what I drink and eat.
Even with the daily does of the PPI I still get reflux attacks sometimes and can never workout what triggered them off.