Im in love yes. You get butterflys in your stomach just thinkin bout them,miss them even if there just on the loo!! Cant keep your hands off one another.You feel sick at the thought of not being with them or seeing them again
Joined at the hip syndrome... can be remedied by a crow bar.
You will notice that the eyes of your friends begin to glaze over when talking about your beau.
In extreme joined at the hip cases your friends may also turn green, start vomiting and occasionally look for the large thumb print on your head. (They're not actually looking for a thumb print, that would be silly, they're looking for your lobotomy scar).
I think the others have answered the general things.
But I think you just know really. Whenever people said that to me, I was like 'yeahh, whatever'
But now I truly believe it.
Also you have to think about what life would be like if you never ever saw them again.
If you have to ask if you're in love then you're probably not. You WILL know when you're in love.
I'm not sure that butterflies in the tummmy and can't stop thinking about that perosn indicates "love" though. I have that feeling about someone right now who I've only been out with a couple of times (so I'm not in love yet) - I'd say that was lust and a crush and the first bursts of excitement of a new relationship - not love. Although I do agree that these feelings still happen when you are in love with someone it's just they are not the only things.
Love is much deeper and emotional and has a security and comfort as well as all the stuff mentioned above so if you're ONLY experiencing butterlies and thinking about them all day don't assume it's love.