For those who have experienced love at first sight, please share your experiences.
Were pheromones involved? 
Understanding the Chemistry of Love Relationship Center
"At the risk of putting a damper on your passionate memories or your favorite fantasies, what exactly is going on when you feel that tingling feeling all over? What causes that initial hormonal explosion? Falling in love is actually one of the most thoroughly investigated and well-understood phenomena in the relationship field. When we meet a person of the opposite sex, we are mentally sizing them up to see if we want to mix our genes with theirs. We then put the object of our affection to certain tests. First, we check for symmetrical facial features (evenness is a reflection of healthy genes) ─ men scrutinize women for curves (which represent fertility) and women generally go for a tall mate and will often choose kinder, more nurturing (feminine) features, over harder, more classically-masculine faces. In other words, women will more often choose Matt Damon over George Clooney, if they are looking for long-term love. Once our brains have scanned the other person’s physical attributes a flood of chemicals and hormones are released into our system ─ the chemistry of love. Now we begin to evaluate that special person across the room under the influence of dopamine, norephinephrine and phenylethylamine . Add to this mixture a surge of adrenalin and testosterone and your heart begins to skip a beat and boom ─ you’re in love. It should surprise no one that all of these chemicals are also released during sex, and occur in both men and women.
Unfortunately, those magical first sparks soon disappear, unless you take steps to keep them alive. After a period ranging between eighteen months and three years, our brains become less reactive to these chemicals and the levels begin to drop. The good news is that with the next phase of love come feelings of warmth, attachment and closeness. These feelings are accompanied by another hormone called oxytocin, which is associated with intimacy, caring, and mother-child bonding. In other words, this is the point when momentary lust becomes long-lasting love.
Couples who are successful together for the long haul are able to master the challenge of creating a shared identity for their relationship. Although the relationship is comprised of two distinct personalities, it needs to develop its own unique personality, transcending each of the individuals. Couples who do not respect that third personality ultimately suffer when they are confronted both with problems from outside of the relationship and internal conflicts between themselves.
Obviously, success in relationships involves a lot more than just hormones. The way that the couple treats each other when they fight is much more predictive of long-term success in marriage. In addition to dealing with conflict, nurturing the following ten elements of their relationship will improve a couple’s chance of keeping their love alive long after that first spark dies down."
And will deny everything to the contrary. 