You must fill it in, if you don't and have an accident then your licence will be invalid ,as will your insurance.
Have you got the right form?
If you are the driver of a bus, coach or lorry or 'large vehicle then you wouldn't have had a chance at a licence a few months ago and you will need records going back 3 months plus a specific medical
From what you've written though it sounds as if you are a car driver.
I don't think many get called for a specific medical (never heard of one except for vision when there has been a problem but I suppose it could happen if they can't get a report from your doctor ... (eg if I tried to renew my UK licence they might do it since I have no UK doctor)
Have you got the correct form and the guidance as to how to complete it?
DIAB1 and Guide to DIAB1
https://www.gov.uk/diabetes-driving
If you've only ever had one hypo, then no problem. Even if there were more
we need to know if you have had any
episodes of severe hypoglycaemia in the last 12 months.
●
If you tick YES you should only count episodes where
you have needed another person to help you
Note that is needed, not just a kind OH getting the glucose tablets for you.
The number plate test is the same as for all drivers
and the rest of the eye questions should be a no, unless you have loss of vision to an eye, laser for retinopathy or cataracts.