Lots of good info here. I would ask this, what’s your BG (blood glucose) levels? Have you been tested for diabetes? If you have been tested, and your HBA1C is good, then up your carb intake.
You mentioned feeling better eating a banana. I would recommend upping your carbs to about 100 grams a day. You should be able to get into ketosis, albeit a bit slower, but get there still. The reason I ask about diabetes is those of us with diabetes have a harder time staying in ketosis with more than 20 grams of carbs. I went 0 carb just for this reason to get my diabetes in check ASAP.
Now, that said, of course this is not medical advice. I’m an electrical technician, not a doctor. But I can pay attention to details and see trends for myself. Anyone can do that, as you did by mentioning your test. I would recommend against most fruit though. Fructose isn’t very friendly to the body. I would go with the standard starchy carbs to get your carb boost. Something that doesn’t interfere with you gut. Explore your options. Most importantly talk to a doctor about it.
Do keep us all informed. You came to a great community of caring people.
Take care, don’t stress.