Messenger - If your video sharing with one person and another person see I'd your in a video chat?

First if your in the middle of a Video chat with someone it will say Active now,there will also be a green dot visible.This is visible to anyone that's looking.If your Video chatting with someone can the other person see when you message them while in the middle of a Video chat?Actually I've had this happen to me,The person can not see any messages that are being sent while they are in the middle of a Video chat until they end the Video chat.The circle next to the message with the check inside of it will stay clear until after they are done Video chatting then the circle with the check inside will be filled with blue immediately after the call has ended.