Hi Petal50,
I hope by the time you read this you are feeling better.
We all have days when we over do the carbs, my downfall is chocolate peanuts from M&S, just because I can eat a few and not dent the bg reading I scoff the lot :roll: . The thing to do is not be too hard on yourself but resolve to get back on track as soon as you can and you can do it.
Think back to when you were dx'd, when you learnt about low carbing and resolved to do that, how did you feel, hopeful perhaps, looking forward to your health improving. Remind yourself of what you decided to do to bring your diabetes under control and start again. It's a bit tough during the first couple of months and there is so much info to wade through but keep trying.
When you have your HbA1c blood test this will inform you and your doc how your bg averages out over the past three moths and that will give your something to work on.
Keep a food diary, note down what symptoms occur when, note your bg readings too. I have some berries or an apple or pear rather than grapes. You can ask for grilled fish with a small jacket potato or a few new potaoes rather than chips, in most fish restaurants if you want to eat out. There is always a way around these things, so keep trying. I am sure you can find good food advice in other posts on this forum which will help you