Hi there,
Porridge, brown bread and bananas are all predominantly carbohydrate so might not take your blood sugar down as quickly as you'd hoped. I would suggest trying to keep on the straight and narrow with your diet, and maybe exercise a bit more. Keep monitoring your blood sugar regularly. If it remains high then consult your doctor. They may want to adjust your medication levels. I doubt you'll need to go to hospital at this stage. Try and keep calm, do some relaxation, stress and anxiety can also adversely affect your levels.