When it comes to hypoglycaemia.. do net carbs vs total carbs matter? which one should i pay attention to?

Glycaemic index: Will tell you how fast a carbohydrate is likely to be released - see below. https://www.baus.org.uk/patients/conditions/2/blood_in_the_urine_haematuria If you are hypoglycaemic then I'd recommend 2 things - a doctor visit to work out why and rapid administration of a source of glucose e.g. juice, candy etc to rapidly normalise blood sugar and then seek urgent attention to work out why.

Hypoglycemia: When patients think they are "hypoglycemic", they are typically referring to symptoms that they get either before or after eating that may be relieved by eating. However, very few people are actually found to have a truly low blood sugar causing their symptoms. I typically recommend obtaining a home glucose meter to test your fingerstick sugar when you are having symptoms to see i it is low

Consult a dietitian: The human body can easily convert the "carb stores" equal to about 12 hours of blood sugar kept in the liver. It can also convert protein and fats to glucose. These are fail safe properties the body has to keep your body going if your blood sugar dips. Medical conditions requiring constant carbs because they don't store carbs well need one on one consultations with a dietitian.