I'm not sure if I don't know my limitations or that I do but just choose to ignore them. Case in point... I'm getting over a case of strep throat. It knocked me for a little bit of a loop, but not too bad, considering. I only took one day off of work, though I could probably have used at least two. Tonight I convinced myself I was feeling good enough to go to the gym. Working out was pretty tough. I didn't realize exactly how limited my lung capacity was until I got up on the elliptical. I was ready to quit about twelve minutes in, but I pushed myself. I told myself I could quit at thirty minutes. Then forty. And so on and so on. Needless to say I pushed myself all the way through until my hour was up. And I felt both amazing and horrible. I had that post-workout rush happening all at the same time I wasn't able to breathe. I've been home for about 45 minutes now and I'm just about back to where I was before heading out in the first place.
I really, really need to learn to recognize and respect my limitations. It's something I've never been good at, but something I desperately need to work on.