Me too. Rest when your body tells you too.

I describe the feeling as "hitting the wall" - if I ignore what my body is telling me to do - it just gets worse. A couple of times I've ignored the signs and then I'm so exhausted I can't sleep becaues my legs go all weird on me and I get very sooky and hopeless. Now I've learnt the signs I make a hasty retreat from whereever I am about 30 mins before I hit the point of no return.

I can't imagine what its like on your subsequent pgs or with a high powered exec job.