Hi Tinlou,2 pillows can actually put pressure on your stomach and create more chance of reflux. That's the idea of the wedge...it's a more gradual elevation, so it doesn't bend the top of your body to create that pressure.
If you're having more reflux at night, you could try a different sleeping arrangement. I have used the wedge and an elevated head-of-bed, and the elevated bed is much more comfortable in my estimation.
Good luck finding an answer!
Denise