It seems from your history that you have a condition that is related to the parasympathetic system. Since the parasympathetic system is involved in arousal. Also, it is sometimes involved in straining of the neck as the vagus nerve
, which is the most important parasympathetic nerve, gets compressed when you lift heavy weights.
You should consult a neurologist
or a physiotherapist who will be able to help you with the exercises so that it will relieve the compression.