Question about love

Hey everybody, I've got a question and I didn't know where else to turn. I've been going out with my girlfriend for about 3 months now, and I love her with all my heart. Or at least I think I do. I tell her that I love her and she tells me the same, and this is the strongest I've ever felt for someone. So here's the question: How do I know if I'm in love? I know this seems to be an impossible question, and I'm not really expecting any good answer, but at least a little bit of guidance. If anybody has any ideas or advice at all just let me know, please.
- Anthony J. Gavin

It's similar to the feeling you get right before you vomit.

do u feel funny in the tummy, like there's a butterfly floating around??? well man ur hopeless man, coz now ur officially a wuss....u don't know if u love the person until at least a year into the so called relationship....ok i'm gonna give u a coupla tips, let he initiate the i luv u statements...and what the hell u mushying up for man....don't b a jerk but keep ur cool and well have fun man...i guess thats what being with the person u 'like' is all about....don't b boring and predictable, coz she'll definitley move on, u c girls prefer excitement and stuff like that during the initial stages, and then gradually decrease the tempo, but don't kill it completely until ur like 90 or something...the best thing u can do is make sure u don't mushy up too much...do sweet things once in a while, that way she'll cherish, don't make it a chore and then ur efforts won't b valued. all the best anywayz