I went through the same thing with Tori, but she has gotten much better now. She has 3-4 naps a day of between 45mins & 2 hrs. Do you swaddle him? I didnt used to swaddle her during the day but as soon as I started she started sleeping for longer.
If you are worried about reflux have you tried propping up one end of the bassinet? Also I rolled up 2 cloth nappies and put them either side of her in the bassinet to help her feel more secure.