It is never too young to fall in love. But you have to watch yourself so you don't fall for someone because you think you're in love with him. The best thing I could advise you to do is to give it a couple of weeks to see how you feel about the person. You might think this is a long time but if you are really in love then what's the rush? So if you're in love then go for it.
Answer Personally, my answer would be that 14 is probably too young. At that age, a kid has only just finished going through puberty, and they're still working on figuring out what love really is. Although it's easy for a 14 year old to become infatuated with someone, the feeling is usually pretty shallow. I think the minimum age is more like about 15 or 16, which is also the age when most teenagers seem to decide what kind of person they want to be and what goals they want to have.