Now the blood sugar readings are in a normal range and i'm noticing when i haven't had anything to eat for 3 hours I start to feel shaky and a bit spaced out. I also notice it happens quicker when i've been exercising or bike riding.

I took a reading on one of those occasions recently - to see if it was low blood sugar - and it was 4.7 - so a bit low, and the lowest reading for me. So I guess I just go a bit hypo under 5.