Not everyone is suited especially for science. It really depends on your personality and learning types. Science consists of a lot of facts and learning, which equals a lot of studying. It isn't something that you can cram into one night before a test and forget about it later; the knowledge all accumulates. This goes along with physics and chemistry, which are heavy in mathematical calculations.
Science is a very demanding subject, especially as you go higher up in education.
So at the end, science is a fascinating subject about the quest for knowledge in almost every area. You'll learn the most facts that answer all your questions about "why or how did this happen?"
Although it may be hard, that doesn't mean it's not fun. Science is a heck of a lot of fun!