It may not even be OCD actually but maybe more generalized anxiety since you haven't had other thoughts.
It seems to me that there are two things you can do to really help yourself and that is to quit smoking and to come up with a diet plan. Since you are obese, I would recommend that you see a nutritionist to help you with that. I think once you have these things taken care of, you will feel much better.
No i dont have any other thoughts
I did ecg and echo and every things is ok but the thought about my heart rate does not go away ,, any anti ocd for help?
So you are having obsessive thoughts about your health and your heart specifically? Have you ever had any other obsessive thoughts or is this something new for you? Also, how is your health in general? You mentioned two things that are not good for the heart, i.e., smoking and obesity so I'm wondering if you saw something somewhere that got you thinking.