What Causes Tightness In The Chest And High Blood Pressure?

I'm a male, 48 y/o, 5'11" 185 and in really good shape....I have a pretty balanced diet, etc. I have been pretty dizzy off and on for a few days, thought I actually might have been hypotensive based on a past similar experience (not staying hydrated enough here in the Southwest Desert). I've had some mild discomfort on my left side (feels like cotton in my left ear sometimes) no chest pain and my heart is not racing but it feels "different" than my right side - there is a little tightness below my left pec. I stopped at the drug store and checked my blood pressure and it was really high but came down after the third check (165/95) down to (133/83) - I did have a couple of strong coffees at lunch a few hours earlier. Should I be concerned (no recent stress and not trying to be anxious about this but I am concerned - I've been a healthy athlete).