I am not a med professional, but as someone who, because of thyroid issues, had blood pressure and pulse readings all over the map within minutes, I can tell you that it is not unusual for your blood pressure to change significantly between testing. For that reason, blood pressure is best looked at over a period of time when readings are taken at the same time more or less of the day. Then, the average gives you an idea of your baseline for your blood pressure.
What I would suggest, though, is that you consult a medical practitioner to have the results of the ECG explained to you so you understand what the test results mean rather than treading emotional water trying to figure them out. For example: a blood pressure gauge and an ECG are two different tools that look at different types of input . . . ECG based on electrical impulses and blood pressure based on frequency of blood pulsing through a major vein. In other words, they both look at different but complementary aspects. As the person who is obviously in a state of anxiety over the meanings of the tests and the results, you need to get centered so you understand them from reality brain's perspective rather than letting anxiety brain create unrealistic intepretations for you.
As LindaRK says, I am also pretty sure that had the doctor seen anything on the tests, that s/he would have followed up. But, you also need to ask questions so that anxiety brain is not given the opportunity to create issues for you. So, my suggestion would be: either accept that the symptoms are anxiety related or, contact your doctor for a fuller explanation and, if the cause is not physical, then ask for a referral to a counselor to help to guide you to develop management techniques. In either case, though, let us know how you are doing because most of us, if not all, know how debilitating your situation can be when you don't have a strong answer to your concerns . . .take care, kc