My left leg has been aching for the past few days at the same time ive been getting a feeling of tightness right below my left collarbone. both started at the same time. whats going on? could this be relayed to my heart?

No, those symptoms are unlikely symptoms of any cardiac condition but I could not correlate those symptoms in one medical condition although both occur simultaneously. Just observe for now and recontact us if you have any other new symptom such as shortness of breath, leg swelling, fever, etc. You can take advil OTC as needed for a day or two in the mean time. Good luck.