From what Ive seen and read, I think the mast cell issues attacks can present differently in people. My uncle when he had an attack of systemic mastocytosis (as he lives interstate, I only seen him once at a funeral..and he had an attack there)... from my observation of his attack (so of cause I couldnt "see" any invisible symptoms he had) .. but he went into breathing issues (he had to be put onto oxygen due to the breathing issues) and had a near collapse (he was left unable to walk.. before that.. he started to stagger). He also was hard to communicate with while this was all going on... so brain fog/trouble thinking and speaking.. speech went very slow and like stammering as he struggled with his brain. (with him.. i couldnt see any skin symptoms.. his excessive mast cells are internal.. He thou did look ill)... and I assume he got a headache by the way he kept on putting hands to his head. (my uncle goes into anaphalactic shock with his attacks). Other people get things like swelling during an attack. The symptoms I suppose would all depend on where the person had excessive mast cells and in which organs they are in.