It could be a sort of hysteria especially if her reaction wasn't what she was expecting, she may have subconsciously created a reaction to counter the negative reaction she hadn't expected and the reaction has just escalated. So instead of feeling relaxed, warm, nice,etc what she felt was dizzy, nausea, cold, anxious, paranoia, etc. Then for whatever reason, panic maybe, she has subconsciously created a different set of effects that have spiralled out of control. I guess if it is a wierd sort of panic attack then you could see if she is hyperventilating and get her to slow her breathing, see if that helps.