Hi, Welcome To HCM & Thanks For Asking Your Query Here As you mentioned that you use inhaler means there are some sort of breathing issues are there with you which you did not mentioned but if you have any lung or pulmonary disease such as COPD , asthma , pneumonitis etc or any cardiac disease like angina etc then your problem may surely be related to that and needs medical assistance but if u r otherwise healthy person then Chest tightness while taking deep breath can simply be related to the chest muscle as when you repeatedly try to breath deeply your lungs expands to their maximum limits and apply pressure on chest muscles which may be the reason of your pain so finally i would strongly suggest you to see Your dr , along with physical check up he may go for all necessary medical investigations to rule out any underlying medical condition I hope it help Thanks & Get well Soon