Shock getting “unstuck” when starting to drive

[cantstoppluggin]

Hey guys, my first post here. I would like to say thanks to everyone for sharing your knowledge and helping all of us.

Basically, I got a problem with my rear end. Whenever I start my car and try to drive after it has been standing still overnight it makes a weird sound like hitting a bump and it feels like that as well. Feels as tho my shock would get unstuck. Happens around every other time after leave the car still overnight. Had my car checked last month and had no issues. I have to wait a week or two till I can get to a bmw dealer and I would like to diagnose the problem till that.