You seem to know what caused it so next time if eating more carbs than normal perhaps you could adjust your fast acting to accommodate it. Sometimes we experience high blood sugars for no reason we can work out, it's the nature of trying to manually achieve something your body would normally do automatically without you even being aware of it.
Due to long term damage causing intermittent delayed digestion, nearly every day at some point my blood sugar will reach the high teens or into the 20s, or go too low, sometimes even both in the same day. Despite all this and with a lot of effort now, my Hba1c result is within acceptable levels now, and the last time I saw the Diabetic consultant he said it hat was the most important thing.
When these things happen, you learn from them over time, so don't feel too bad about it, tomorrow is another day, and as long as you don't make a long term habit of having raised blood levels you should do just fine.