Pulse racing, palms sweating and butterflies dancing up a storm in your stomach - the unmistakable physical signs of a person in love.
If you're smiling your way through a day in hell and see sunshine every time it blows a sand storm, the chances are you've met that special someone that makes you forget what you're doing and leaves you so preoccupied that you're half way to the office before you realised it's the weekend and you're supposed to be going to the supermarket.
For those of us lucky (and smug) enough to feel that way, every day is Valentine's Day and a day set aside especially to celebrate seems just that little bit mundane ... but for many out there it's a day of dread and despair, that leaves you feeling lonely and unappreciated. But it shouldn't.
More and more people these days people have forgotten all about the history of Valentine's Day and prefer to think of it as a day created by card companies to increase their sales - the thinking being that a person in love doesn't need to show it on any particular day as it's something that should come naturally on a regular basis.
And, to a certain extent, I can see the logic to that argument. At the end of the day if your man regularly brings home flowers for you or takes time everyday to find a new way to show you that he loves you, why should you need him to make a special effort once a year?
But let's face it, such a man is a rare and wonderful thing and for most, after the honeymoon period is over, love becomes habit.
You don't stop loving the person but everyday life takes over and there never seems enough time in the day to set aside to let that person know how you still feel about them.
Before you know it, you don't even realise that you're not making the time and it doesn't even cross your mind that you haven't told your partner you love them in a long time.
That's when you can thank the heavens for Valentine's Day.
When the streets are lined with shops full of flowers and big red hearts in the windows it's hard to forget it's time to make an effort and unfortunately for you men out there, as much as you might think you can get away with not making a big deal of it, the truth is you can't!
There isn't a woman out there that doesn't secretly want to be made a fuss of and the very fact that you couldn't even be bothered to do something about it on the one day of the year that you're supposed to isn't going to win you any favours.
And a little word of warning for you husbands out there - BEING MARRIED DOESN'T MEAN SHE AUTOMATICLY KNOWS HOW MUCH YOU VALUE HER. In fact, when you're married, you should be making an even bigger effort to show her you're not taking her for granted.
And that's really what Valentine's Day is all about - letting someone know that you value the qualities they bring into your life.
Saying I love you and bringing home a box of chocolates or booking a table at his or her favourite restaurant is all well and good but let's face it, there's nothing original about it and doesn't really show that you care enough about a person to make a special effort to let them know.
If you really want to let someone know they're valued, put some real thought into it and come up with an idea that shows you've taken time out of your day especially to make them feel how important they are to you.
It doesn't have to be grand and it doesn't have to be expensive - it just needs to show that you've made an effort - and you don't need to worry about being corny because let's face it, love is corny and soppy and all those things you don't want to show in front of you friends.
It could be something as simple (and yes, corny) as dropping a line of rose petals in a path to the bathroom where you've lit some candles and run her a hot bath to relax in and enjoy while you put the children to bed and unpack the take-away you picked up on the way home from work.
It doesn't matter that you haven't cooked the meal yourself, what matters is that she doesn't have to cook it. Make her feel special for just one day and you can be sure it will put a smile on her face for a long time to come.
As for you women out there, Valentine's Day isn't just for us.
As much as you might think that the day is all about your man showing you how he feels about it, it's about them too. While it's traditionally a day where the man is supposed to make the effort, don't forget it's about love in general.
It's about making sure the person, male or female, in your life knows that they're cared for and appreciated.
As for being single, you are not alone.
There are loads of people who go through Valentine's Day without a partner to share it with and that doesn't mean that it isn't a day for you.
Love can come in all shapes and sizes and isn't in any way exclusive to couples.
Each and everyone of us has an intrinsic need to know that we have love in our lives and family and friends are just as important to show it to. Send your mother some flowers or take you best friend out for a slap up meal.
Whatever you do and whoever you do it with make it a day where you show someone that you're happy about the difference they make in your life.