I am concerned about the angle/slope/fall of my drainage pvc piping under my sink. My horizontil pipe after the trap is level. I then checked each pipe drain connection (3 of these) to the wall. The slopeof the 1st connection after the horizontil pipe is away from the wall and toward the horizontil pipe (falls back toward the horizontil pipe). The 2nd connection toward the wall is also sloped back toward the horizontil pipe. The 3rd connection is also sloped toward the horizontil pipe. Their is no falling but their is a rising in slope from the end of the horizontil pipe to the wall. Is the slope or fall supposed to rise in such a manner? Do I contact my contractor to have this replumbed or corrected or will I be laughed off?