Love forced through magick is as good as pretending...it isn't genuine.
Such things are temporary and usually backfire, not because they're bad, but because they're artificial. You're messing with someone's emotions and thoughts, then your influence goes away and one of two things happen. They get a sudden shock of reality that is extreme and causes them to behave in the opposite way on impulse or they accept it as a natural part of themselves and can become obsessive with it. That all depends on will power and personality.
Directly influencing other's is best used when you only need one time, temporary effects. Not only is it easier but it also leaves no trace.
If you like a girl and you're set on using magick, I suggest carrying/wearing a rose quartz, put on your best smile, bring her a single red rose, and ask her out. If you need further confidance, you can charm the rose to increase your success of her saying yes to a date. Then it will be just you and her (no influencial magick) from there.