Bibi, he sounds like he is 'normal' reflux baby. All my 4 have/had reflux in its varying forms. As they get older it tends to get better, some faster than others.

With sleeping, does he sleep on his back or his side? Most babies with reflux will still get pain while sleeping on their back, even with the mattress/bed elevated. When putting my little one to sleep on their side I use a special bolster to keep them from wriggling onto their tummy.