Dont panic, chances are because cheese in general has little carbs you are in Ketosis...
Its so easy to throw something into the gob. Lord knows it automatic at times, but you are breaking a habit and you noticed that you did it...and as you said - you dont know why...
I ate 5 tangerines once, and my ma was like - steady on... i was like - jeez it was only one...but i ate the other four off the bat and didnt even realise it...
It was a wake up call. and this will be yours.
I am amazed you only stopped at a few maltezers tho - so be proud that you did rather an berate yourself.
i'd have munched away at all of them. Cos they taste heavenly.
Dont panic, you havent failed. you have opened your eyes and in a way thats better than sailing through and not realising the tendency of 'invisible' eating where you dont realise your actually eating...and hence overeat and are biguiled as to why the weight isnt shifting
Ivy