30 is young, you'll be fine. The tricky part (for me at least) is the memorization. After 20 years of working in a field where I can look up everything I need

30 is young, you'll be fine. The tricky part (for me at least) is the memorization. After 20 years of working in a field where I can look up everything I need to know, suddenly I had to commit thousands of data points to memory to pass a test (then promptly forget the data afterwards). It's an archaic system. Anyway you'll have to find a way to memorize and regurgitate. If you can do that, the rest is just common sense.