Before diagnosis I was regularly tired after meals, falling asleep uncontrollably (including during the occasional meeting - oops) and at times in danger of falling asleep at the wheel. This is because my BG was hitting around 19 and my HbA1c was 10.8.
Its a common effect of high blood glucose (BG) and other symptoms can be constant thirst and urination (particularly overnight), mood swings, depression and generally feeling rough.
When I got my BG under control, the difference in how I felt day to day was incredible. I hadn't realised just how rough I had been feeling until it all changed. It had crept up on me.
So it sounds as if you are running high numbers and if this goes on for a long period, you will be suffering damage, so its vital to get it sorted out.
The reason your nurse does not think you should be testing is that the majority of T2 diabetics do not actually test for any reason. This is mostly because they have been told to test once a week first thing in the morning or something similar. This tells you almost nothing.
However, testing can be used to learn about the effects of combinations of foods and exercise on your BG. As you learn from this, you can make changes to what you do next time to keep your BG at a more stable level. So over time you learn how everything affects you and how to deal with it. We all react to everything slightly differently so although people can give tips on what effects things have generally, you may react slightly differently. So some of the time it can be quite personal to you and the only way to learn about that is to test.
The following link is to an article which has helped me and many other T2s to begin to learn about managing diabetes. The emphasis is on learning how things affect you personally and making changes to your diet and lifestyle that work for you. Its not about following a particular diet plan or regime, but generally means making adjustments to your life so that diabetes fits into it. It puts you in control. Plus, by getting control you will massively postpone or completely prevent long term complications .
http://www.diabetes-support.org.uk/joomla/jennifers-advice
Hope this helps.