My reccomendation would be to take up binge drinking for a few years. The benefits are incredible:
1. Even with your level of motivation, binge drinking will allow you to drag out college for at least 3 1/2 years, probably 4, thus making you older when you enter law school
2. You will be able to make friends and network in law school much easier when you get there because you will be viewed as that likeable super genius who knows how to party AND manages to be very successful instead of as that super genius 19 year old kid whose voice sounds like nails on a chalkboard and who has probably never been laid.
3. The girl problems you mentioned will dissappear. I've always found that the more I've had to drink the easier it is to find girls at my intellectual level.
4. If you're lucky you may even be arrested for something stupid like pissing in the middle of a crowded street or getting into a barfight with a cardboard cutout of David Hasselhoff and have the opportunity to experience the legal system as a participant before even entering law school.
5. Once you get to law school, not only will you actually be able to attend sponsored social events held at local bars since you will be of legal age, but you will actually be able to hold your liquor when fellow law students are trying to pour it down your throat and get you to say something stupid to your contracts professor who is chatting with one of the deans nearby.
...In all seriousness though, I wouldn't reccomend anybody under 21 start law school. No matter how smart you are, I doubt that you will have the emotional maturity to handle a lot of the crap that comes along with attending law school. On top of that you would be a total outcast because of your age. Obviously you don't have to be a binge drinker to make friends, but you're going to find that you cannot attend a lot of social events just because of your age.
I'm going to be a 3L this coming year and I'm 24 years old. I have a 19 year old brother, who is smart as hell and a lot more mature than most kids his age, but the fact is that I still view him and all of his friends as kids because they just don't have a lot of life experience. I can't imagine that a 19 year old who has spent enough time locked inside a room to have finished college and be ready to enter law school would have even LESS life experience than someone who has taken the normal path to those accomplishments. Kids don't belong in law school. I actually wish that I would have taken a year or two off before entering law school because by this time next year I will be ready to begin a career that is likely going to leave very little time for me to enjoy my life the way some of my less ambitious friends from college and high school will be enjoying theirs. Once you start law school there is no turning back, because taking time off after law school is greatly frowned upon by both employers AND debt collectors.