Some showerheads work much better than others. By law, you cannot buy a head that flow more. Now, on some of them, you can remove the restrictor (often just a disk on the inlet). Think about buying a new showerhead. Make sure that the inlet screen of the head is not clogged, first, though. At only 1-1/2 years, it shouldn't be all limed up, but could easily have junk from contruction clogging the screen, or maybe sand if you are on a well.