Hi, everyone, thanks for all your helpful answers re my current 7-week + crash with new symptoms. I'm feeling a *bit* better and am trying to do a little more without overdoing it. Before this crash I had ME symptoms, but strangely not post-exertional fatigue, except for 1-3 day crashes that seemed to only come after a lot of stress. One of my new symptoms is a feeling of tightness in my heart/lung area, esp when I go for a walk (presently about 10 minutes). This makes me much more worried about physical exertion than in the past--I'm also really anxious not to relapse b/c I have to move in 4 weeks. Relapses have happened 3 times during this 7 weeks, but each time is was after 2 days of social/mental exertion (two trips out of town, one intense visit from parents), with some walking around the first 2 times. While I don't want to relapse, I also don't want to just assume I "can't" walk a bit farther (200 steps) each day. I'd really love to be able to get to the grocery/drug store and back (I can get halfway now). I could do this before the first relapse (week 1) without worries, and worked up to it after the second one (week 3). Maybe I'm too attached to the idea of measuring improvement, though. As this has never happened to me before, I have no previous yardstick to use. Is there any way of knowing if I'm going to overdo it before it happens? Probably not but it would be great to know what your experiences are. FWIW, I use a heart rate monitor when walking and it never goes above 90. Thanks!