Your penis is average size, but if you are overweight, have wide hips, large fat pad, etc... it will be perceived as smaller than it is, especially at your height. Your penis length will not change by losing your fat pad, but it will look larger to both you and your partners. This is why most pornstars are short, lean, and have very little fat pad. I would focus on getting into shape first, and maybe do a bit of PE on the side.
Good luck.