I am in paramedic school now and I work as a basic part time. Part time for my agency means I have to pick up a minimum of 3 shifts/month. When I started class in January I was working full time hours (at least 36-48hr/wk), volunteering part time (4 shifts per month) and going to school (one day a week 8-5). However now I am working less hours, I took a leave from my volunteer position and going to school. Come June we will start clinicals and I need to plan to schedule about 100 hours per month of clinical to finish on time or a little early. I am only working 4 shifts for June. Our class ends in December just for a time frame reference. The thing to remember with medic school is it is possible to work full time and go to school full time, but you have to decide how you are going to learn best. For me, I need the study time, thus I stayed part time, but in the 22 people in my class only me and one other gal are part time, the rest are full time. It's all a matter of how well your brain works on a little sleep (part timers) or no sleep (full timers).
If you really want it, you will make it work either way, don't forget that!
My suggestion is to start learning now. Ask your paramedic partner to show you what they see on the ECG (even if it's normal), ask them what drugs are for, ask patients what they are on meds for, study some medications weekly, and most of all practice your assessments, because in medic school you need a strong background in assessments.