You may fall for each other fast and hard, with a strong and immediate mutual attraction; but if the heat between you dies out just as fast, don't be too surprised. The excitement and electricity of this connection just may not be sustainable, and even if they are, you'll still need to get to know each other before you can know whether there's really something deep and valuable between you, something that can last long-term. If this does become a committed relationship, you'll need to give each other plenty of freedom to make it last.
Otherwise, you could stifle your connection before it even gets off the ground. You'll also have to learn to live with unpredictable emotional highs and lows; your romance may well be characterized by drama. If either of you tends toward jealousy or possessiveness, you'll really have to keep those impulses in check, or you'll only increase the drama between you. Your best bet with this affair will be to avoid any and all expectations. Just let it follow its own course and define itself, and be prepared to let go when the time comes.