Science is my worst subject. I was pretty good at math until I got to Trig. I rocked at Geometry and I actually liked that class....proofs were fun, because it made sense to me. But equations and things like cosign and tangent lost me...I just never got that. Or Logarithms. My kids both got their dad's math brain, thank goodness. My husband is an engineer....lots of math and science. I was lucky with physics that we never had any tests. Our teacher thought we'd learn more just by doing the science...lots of labs. I didn't necessarily understand the principles, but it was a pretty easy A as long as you participated. Calculus, I spent pretty much every morning in my teacher's office before school started, because I could get it when he explained it to me....it seemed to make sense, and then 5 minutes later, I couldn't remember what he said.
There are different kinds of being smart. Some people are really good with putting things together/building/creating, some are very creative and artistic, some can memorize facts and dates, some have an intuitive sense of movement/athletics, and some are really good with people....born leaders. Just because math and science are hard doesn't mean you're not smart.