Welcome to HCM
We understand your concerns
You are a healthy man with hopefully good habits, I presume. Doctors did investigate your case and ruled out any heart troubles. If TMT and other heart related tests are done, then it is clear that your heart is out of danger. Then there is some lung problems which is usually accompanied by cough
and breathlessness, which you don't have. Third, there can be injuries or bruises to the intercoastal muscles which can be cleared with pain killers. Fourthly undue worry and anxiety
about health condition can make you feel pain even if there is no pain. That is psychological. For you the last one might be the case. You need counseling an may be psychotherapy
. Consult a psychologist
or I can help you online if you desire so. Get well soon.