Last evening without exertion, my heartbeat was 110, 10 min. later, it was 118, 10 min. later, 129. It was regular and my blood pressure was normal. I had not had any caffeine since early morning. However, I did have a shrimp coctail prior to the increase and am wondering if I had a reaction to shellfish. I've always had normal blood pressure without any meds. I am 57 years old.