OK, so here's a fairly unmistakable sign that you are in love, that you had a strong feelings for  someone, and that it wasn't just a passing fling. And it comes from the author Stendhal, who says that having an air of intensity is a sign of being in love; this means that love acts as an intensifier of emotion, causing things to become more beautiful or tragic. A small gesture from your partner can cause you to overthink and overinterpret what they're trying to say. You become exposed, like a raw nerve. And yet, this intensity causes you to see beauty in the world around you, to believe that you don't need other people to be happy, that you could be sitting on the couch with your loved one, with your toes touching, and have everything you need in the world to be satisfied.

Love is an intensifier, but it can also cause pain.

Intense feelings are a sign that you are in love.