My belly button is stretching beyond belief!!

Lol! So my fiancé was just starring at my tummy saying wow, and when I asked him what he was "Wowing" he grabbed my phone and took a picture of my navel to show me. I've always had a innie that I've never been able to see the bottom of and its stretching like crazy. Is anyone else experiencing this? I would assume it's normal but I'm just freaking out! Hope I'm not the only one! Any input?