<s>[INST] what does it mean when my chest feels tight when i take a deep breathe i have only had it for about 2 days but its a different feeling i have never had this before even when i yawn or hickup it hurts a little i dont know if its my lungs or heart what could this be?? and is this serious? thank you [/INST] Respected user , hiThanks for using Healthcaremagic.comI have evaluated your query thoroughly .*  There are various reasons as  - Conditions of lungs ( infection , pneumonia , effusion , allergy , others )  - Problems of chest wall ( muscle stretch , sprain , blunt trauma , costo    chondritis , rib fracture or inflammation )   - Heart  related ( valvular disorder , cardiomyopathy , ischemia , infarction atherosclerosis )  - Pericardial conditions   - Diaphragm problems * In short this needs extensive clinical work up with expert physician check   up and series of necessary tests to find the cause .* DO NOT NEGLECT it and get an appointment with your PCP .Hope this will help you definitely .Welcome for further questions .Regards dear . </s>