Hi, congrats on your new little bub!
This IS the time that many folks start to see symptoms in MPI babes. I will say that at 3 weeks old my daughter was a mess, with the symptoms you described, plus horrible muscousy loose stools with blood in them. Also screaming when laying down (we also had reflux and over supply,,,.yeah, good times).
However, lots of babies simply are a little spitty, and their digestive system is maturing and all that you described is normal. Can be difficult at this stage to determine without eliminating milk and/or soy. Are you seeing any strange stools? Loose, mucousy, any dark specks? Is it interfering with sleep? Fussiness while awake or laying down? If no, I would probably say proceed with caution, keep an eye out if the other symptoms pop up and go with the flow for now. Ph, my DD1 had AWFUL baby acne, started at around 4 weeks, but she had no intolerances.
(((hugs))))