Well, if you are sure about that.......my BP is always around the 110/65 level but I have had the odd incident or two where it shot up to around 197/120 and that is when I felt as you described. I check my BP at home frequently and give those readings to my GP/Nurse/Endo etc.
My Consultant wasn't sure if it was medication induced, as I was taking some pretty powerful anti Cancer drugs at the time, or just a 'glitch' which seems to have no real explanation. Been fine ever since.
You might also be just going down with something, a 'bug' maybe. There are many things this could be down to, most are not Diabetes related. I would definitely get it checked out at your GP's, especially as you say it doesn't seem to relate to Bg levels.
Ken