Congrulations on your weight loss! Nonetheless, despite our efforts, lifestyle changes don't necessarily obviate genetics and age. You really should discuss your symptoms with your doctor.
OK, frankly your weight, age, and gender do put you at some risk for cardiovascular trouble, as I'm sure you know.
On the good side, though, you've recently had a normal EKG, and not too long ago a normal echo.
Really, there's no point in being extra worried right now, because you will have another echo this weekend (I hope it's a Stress Echo?), including a peek at your carotids. Your concern is understandable, though, because all this heart business is probably starting to feel pretty real just now.
Your newest tests might show that you can be managed with medication, diet, and exercise alone--or they might show that you need a surgical procedure. If your carotids need to be reamed out, I can tell you that my inlaws both had that done when they were in their 80s, and it really was not a big deal. If you need heart work per se, well, that is also pretty routine these days. And you are young enough that you should sail through anything along those lines. It all depends on what your most recent exams turn up, and we don't have enough info to make much of a guess about that.
But between now and your next echo:
1. If you're really worried about anything--anything--at all, call your doctor to ask for advice, and second,
2. If your pain is accompanied by faintness and breathlessness plus a *profuse, absolutely drenching cold sweat,* nausea, or the sensation of an elephant sitting on your chest, call 911 immediately. That's the standard advice for bad stuff, but the chances are that you aren't going to need anything so extreme.