I would like to invesigate your for pathology of pancreas
.Our pancreas contains beta cells which are responsible for secretion of insulin
.Work of insulin hormone is to lower the level of glucose
Tests suggested is Ultra sound
abdomen to rule out pathology of pancreas or islet cell tumour.
or any thing which is causing hypersecretion of insulin.
Most likely i don't feel its related to gilbert.Next time when you have the symptoms just check your blood sugar level by home kit machine.In case you don't have it at home take one glass of glucose water immediately and see if symptoms settles down or not,
Investigations are required to rule out pancreaticpathology.