I Get(if I Get Nervous Or Upset) A10 Second Pulsation

I get(if I get nervous or upset) a10 second pulsation episode that runs throughout my mid section fron my neck down-what is this weird sensation and what can I do about it -im 53 ,175,5'7'-but this was happening when I was 140 about 5 yrs.ago.,with very little frequency . my blood pressure is alittlehigher now,and I have had a thyroid nodule on my throat area for about that long -any connection there?