High fasting blood sugar?

Hi guys, so i pretty much only joined this forum hoping someone can answer this question. When i wake up in the morning I'll check my BG and it will be fine (we'll use today as an example: my sugar was 117 before leaving for work) i didn't eat or take any insulin because i had to get bloodwork later that day, which unfortunately requires fasting. On my break at work, which was about 5 hours after my initial check, my sugar had gone up to almost 400. This happens everytime i don't eat or take insulin when i get up. I've had doctors sort of address it in the past by either fiddling with my lantus or telling me simply just to eat breakfast which in therory is a solution. But even so, that doesn't explain *why* this happens. I know taking some insulin when i wake up will solve the problem, but it also doesnt seem normal for sugar to skyrocket that much from literally doing nothing.. and lets be real.. Sometimes id rather sleep a little bit longer than get up and make food. Anyone else have experience with this? If yes how did you manage to fix it? Thanks in advance :)