M.D.
There are two separate issues - one is the pressure of the water coming into your apartment. The other is the restrictor on the showerhead. Not much you can do about what's coming in. But, on the inside of shower heads, there is a water restrictor. This keeps the showerhead in compliance in areas that require limiting water usage. You can remove the restrictor to see if that helps. https://www.youtube.com/watch?v=dlklQH85Hec
ETA: And for a laugh, you can watch the old Seinfeld episode about this... https://www.youtube.com/watch?v=dlrtQb24Qxw