i have that problem as well and I took Qtips and diped them in alcohol or peroxide and cleaned it out then dryed it w another dry Qtip
Rinse it out in the tub or using a hand wand, dry it carefully with a twist of Kleenex, then finish with a big glob of Neosporin that you spread with the tip of your little finger to make sure it reaches all the crevices in your belly button. It'll heal in a few days. Good luck.