I've been sick for the past 2 weeks and haven't worked out. I tried to do an easy workout today (just the cardio parts if IM3.. NO INTERVALS) and just couldn't get through it. How do I get back into this?
Take it little by little. I've been off about 2-3 weeks, due to vacation, illness, moving, etc. I just started out by doing my step without risers and only doing as much as I could. Then I added 1 more minute of cardio to each session.
Try lowering your step. Or just do as many intervals as you can manage. Don't give up and don't worry. As many will attest, your endurance will improve with time.
You have gotten awesome advice from awesome women already. I just want to add stick with it, don't be hard on yourself and don't expect to just jump right into it. Take your time and do what you can today, it will not take long before you are back where you were yesterday!