What was it like to establish a very deep connection with someone?

For me, sometimes it would go fast—happening in a night. Other times, it happened over a few days or a few weeks. But eventually I would get this trembling feeling in my stomach that told me that what was happening between me and this person was very important.

It didn’t always lead to a love relationship although when I got that feeling, I wanted it to. Sometimes it lead to an exchange of letters or emails or other conversations, but nothing else. It might end after a while just because it didn’t go on to more, I guess.

Do you have a signal that tells you something very important is happening? A sign that you could have a deep connection to this person? Has it happened much in your life? Did you always follow it? What is your sign?