I love what I do, but it can be both physically and mentally exhausting. I did my research before applying to nursing school. I perused these forums, I bought books written by nurses about their profession, and I talked with my sister (who is also a nurse). This was a second career as well, I was 33 when I started school, and I have never regretted that decision.
Nursing school is difficult, and we can tell you that, but only experience will make you understand. You have to go in with the mentality that you can take it, you'll have to rearrange your priorities to focus on school, but it can be accomplished.
Try taking some pre-req's like Anatomy and Physiology, and focus on obtaining an A. One class isn't going to disrupt your routine too much, but it is a good idea of much information can be crammed into a single semester. Learn it, own it, and ace it. If that one class seems too much for you, nursing school may not be the route you want to go.
You will have variety in your work weeks, and sometimes even days depending on where you land your first nursing job. You'll have to critically think, analyze, and be able to teach difficult concepts in simple terms.
Do some research and take that first anatomy and physiology class. Do so at a community college where the cost is minimal. Then decide what you want to do. Best of luck in your future endeavors!