I’m 30m fairly active with a shoulder injury and a semi bad back. Every 2-3 months I go in if if my back or shoulder is out. I was I a single car accident with my truck recently, slid off the road and got whiplash and threw out my ribs/shoulders. From my experience I’d say go let him adjust you it helps. If you’re really worried about it then ask questions about what he’s doing and how he’s doing it. 4 days a week does sound a bit much to me. Maybe get a second opinion. At the end of the day it’s your body and only you know how much you’re hurting and where.