Hi and welcome.
You may have sneaked under the diabetes diagnosis by a whisker, but only by a whisker. Pre-diabetes is in the 42-48 range, so you were right at the top. Plus if you are getting fasting readings at home, of 7.5-8.5 then they put you in the diabetic diagnostic range. I am surprised your nurse didn't pick up on that.
Sorry if this comes as bad news to you.
However, you can look on it as excellent news, if you like. You now have a few months before your next test to get a firm grip on this thing and potentially delay or avoid T2 for years.
It is perfectly doable, as shown by the many success stories we get on the forum.
- but that means some lifestyle changes. Your after food readings are higher than I would be happy with, if it were me. Have a read of this website
www.bloodsugar101.com for all the reasons why.
And post dinner readings like that suggest that you are eating more carbs than your body can comfortably tolerate.
Have you heard of lower carb eating? It runs the full range from a few less carbs, to low carb, to VERY low carb, but we simply cut back to the level that our bodies tolerate. If you have a meter already, you have all the equipment you need, so just test before you eat and two hours later, and if your bg has risen more than 2mmol/l then you need to cut/reduce the portions or switch from the carby foods that caused the rise.
Hope that helps!
Oh, and that advice to eat a banana - bin it! Bananas are full of sugar and are quick release. Until you have tested one with your meter, I would avoid tropical fruit.
If you want low carb snacks that will help you last til your next meal, then these are better choices:
http://www.dietdoctor.com/low-carb/snacks