DAE feel this sudden chest pain in the sternum and it goes away immediately? Or pain when they do a very exhale?

So, I am not exactly the most healthy but I am decent? I am 24, I am pretty short 5’5 and I have some fat at the moment but also a bit of a muscle (my Bmi is 22, I weigh 60kg). I do not have a great diet. I have been from maybe a year or more feeling these pains in my sternum when sometimes I get up or lay down mostly when I am tired (mostly laying down hard). Its a very quick, painful but dull warm pain that goes away before I can even think about how it really feels like. I also have to add that before this I also used to feel some pain in the same area when I would exhale really hard. I have never smoked in my life except for whatever got into my lungs through company, I have taken a puff of vape once and did not enjoy it. My most recent bloodwork was mostly normal, my platellate count was a bit on the lower side (13.8 MgDL).