Sometimes everything, sometimes little bits
the cottage cheese look just means it’s been partially digested. went through the same thing and what helped us/our doctor told us to do was keeping his bottle sideways instead of at a tilt and burping him as much as possible during feeds. also exercises! Pressing his legs into his tummy, bicycle kicks, and sticking a thermometer up his butt can sometimes push the poop out if he’s just having a hard time getting it out
That sounds normal, especially so young. his little body’s trying to figure out what’s going on and regulating by spitting up. Is he spitting up everything or just a little bit at a time?