Belly Distension

I'm a fairly thin guy, but recently have experienced stomach bloating.
No matter what I eat or don't eat, my belly is bloated and I'm often indigested.
I was diagnosed with Gilbert's Syndrome some years ago---so my bilirubin levels can sometime be elevated.
Recent tests show no other liver abnormalities. Stool samples are fine.
No bowel issues.
So, could these belly issues be related to elevated bilirubin levels, or is something else at play?
I've been living successfully with Gilbert's for years, but the stomach bloating and indigestion are new.