Do not blow a small misunderstanding out of proportion today, and apologise when you need to.
You are likely to blow a small misunderstanding out of proportion today and it could become a much bigger problem if you are not careful. You need to talk calmly with the person involved in this and if you should apologise for anything, do it straight away. Do not let this issue linger on, it will only get worse. Recognise it for what it really is and move on.