I know exactly how you're feeling about the stressful math. I will never forget my second semester of sophomore year in college when I took Differential Equations. For someone who always prided themselves on being good at math... I sure was no expert. It was my only bad grade throughout college, and certainly a low point in my college morale. But I dragged myself to office hours directly with the professor, and even though I never feel like I really grasped the subject, I got myself through the final (somehow), and moved on to the next math series, Linear Algebra, which made A LOT more sense to me.
Stick with it. You'll get through the courses that really drag, and you'll fly through the ones that are interesting. This will actually give you some hints at what kind of job to, look for when you graduate.
Lastly - please know that there are VERY few people in the world who actually use differential equations in their real job. As an environmental engineer, the hardest Math I've had to do on a daily basis is basic algebra, and maybe some statistics.
Take care, good luck