Another Blood pressure question

I am 65 smoker, coffee drinker but otherwise healthy. Actually a couple of questions. As a youngster and young adult I always had extremely low blood pressure according to my doctors. It was actually lowest in my 20’s and early 30’s. Over the years it has crept up to 110 over 65 or 70 which my Dr.says is fine. I am worried that my previoulsy very low blood pressure might be my norm and I am actually suffereing from high blood pressure that is masked us normal.

 If I tell a Dr. about how it has been rising they just pass it off and ignore it with no discussion. 

 The other question is could I have had some kind of problem when I was younger causing the low blood pressure that is still active and slowing down the affects of some other problem trying to raise my blood pressure. I have always suspected thyroid issues because they seem to be common in my Italian American side, but never had it tested.