Since I don't walk around anymore except around the house / garden and I avoid substantial physical activities like hoovering my PEM is almost always brought on by "looking at women" which makes it very controllable, since July I have been learning how to fine tune it and as a result I have been able to avoid major crashes ( defined by causing digestive dysfunction ) since august 10th. I've obviously had changes in symptom patterns over time since then but reasonably minor, on I think it was thursday last week though I "looked at women" for about 1 hour ( average ) then not long after started to develop some sort of infection ( felt overly 'burned out' just before going to bed then woke up feeling a sort of sudden existential dread and wanting to shoot myself, and was too hot / fevered to go back to sleep ) I don't know what this virus was because it didn't cause any other symptoms apart from that, but it did disrupt my sleeping pattern slightly and made me feel extra tired, but I started to recover by saturday or sunday. On monday I felt well enough to "look at women" again, this time for 1.5 hours which would be considered long ( didn't expect it to take that long ), but with a 4 day spacing from the previous time that was consistent with my usual sort of timetable, I couldn't see any warning signs during the activity ( can usually predict the resulting PEM with good accuracy based on how I feel at the time ) and I did it in the morning which is the least dangerous time. So what happened this time which was unexpected / different was I started to get this particular symptom whereby a sort of anxiety / heat / tension starts to build up in the chest, generally becoming worse when you do something which is "more stressful than doing nothing", it doesn't even have to be something that you would normally consider to be a stress, for example listening to music, in this case though I was trying to clear a high level dungeon called Naryu Labyrinth that I had never done before, so this would be something that I would normally consider to be quite a lot of effort, although I have been playing this game for 6 weeks now typically for most of the day so it wouldn't be something that I would normally be particularly hesitant to undertake unless I was really tired. About halfway through though I started feeling like I needed to stop and go and rest which is when I first noticed something was unusual. Typically I find that if its a major crash the change will be noticeable on the same day as the activity that caused it, within 4 to 6 hours if not immediately, whereas a minor crash / pattern variation might not even show until the next day. I'm not sure what the specific term is for this particular symptom if there even is one, I suspect some of the people here will know what I mean though even if it doesn't have a name, I haven't experienced it since august I think, but in the past I've had it at the same time as a severe crash that made me bedbound for 3 weeks, as I said its sort of like the feeling someone gets when they have high anxiety ( enough to trigger panic attacks ) except that my mind is completely calm and clear, it tends to get worse at times and calms down while sleeping, but otherwise in general its very persistent and difficult to suppress no matter what you do. Its also very different in feeling from orthostatic intolerance although you feel it in a similar area. Most of the symptoms I usually have from CFS like the muscle aches are fairly tolerable and I can mentally filter it out, but this one is often unbearable, this in combination with when it tends to arise makes me think this symptom should have its own special name and might be particularly relevant to the etiology of CFS. The point is though that basically this virus that I had a few days ago has changed the PEM resulting from an activity to the point where I can no longer predict what will happen, and am getting unexpected symptoms that I haven't experienced for quite some time. Its just a question of whether it a result of the change in immune activation or the health drain on the body caused by fighting a virus ( remember that I said I felt reasonably healthy / functional beforehand though ) As a side thought / joke I wonder if CBT can make me not want to "look at women" anymore, that might actually help in my case.