Sharp Pain in Middle Chest Bone. Guide.

Sir,  My age is 33.  1 month earlier, while climbing stairs in metro station... i felt sudden sharp pain in middle chest bone...as if someone has pressed hard...in center chest bone and  around the chest ...and made me uneasiness for almost 1 hour... This is the first time i have experienced such in my entire life....However, did not experinced again such sharp pain except for minor pain sometimes. Sir, had my full body checkup done..alomost 4-5 days back, in which my cholestrol level has high Triglcy around 159...and Vitamin D range 5 (min range 20). I thought chest pain earlier ocuured may be due to Heart related problem. Went to Cardiologist and done TMT and CT Cornory Angiogram which came to normal. Sir, just google the thing now, and came across term pulmonary embolism. Please guide...whether such pain which occured means pulmonary embolism, having possibly of blood clot or any gastric or acidity . A bit tensed Sir, please guide.