159 on your first try isn't bad at all. It's really disheartening going into the test the first time with some expectations only to find yourself marking incorrect answer after incorrect answer. In the end though the first test isn't a prediction of what you'll end up with. I scored 156 on my first practice test and took a course before my first real LSAT. I ended up with a 156 for my first official score, that was abysmal and a poor representation of my abilities.
I took the Kaplan course before my second official test, which was a year later, and scored a 172. You're not really going to have a good idea of what your potential is until you learn the methods for the test. If you take a bunch of practice sections and find yourself missing 2-4 after a couple weeks of practice you should be in great shape. The practice sections are great to learn the material but this needs to be buttressed with a number of full tests as well. Most people can answer the easier questions on the LR and RC sections taken individually and with enough time, the difference between being able to answer one question or a section and score well on the entire test is your endurance. It's hard to simulate the environment and stress on your first test day so make sure you have the mental stamina to make it through all 6 sections of the test.
Top 14 schools do give you a great opportunity for work
after law school but there are plenty of opportunities elsewhere. The employment prospects for students in the top 10% at a school like Iowa or Illinois are similar to those in the middle range at higher ranked schools. I have an interesting research article that details how school rank, law school gpa, and other factors contribute to income potential as a lawyer, let me know if you want me to send it to you.
Also, you're only a sophomore, chill out. You're going to have plenty of time to worry about law school when you're applying/in law school.