When people have a chronic lung disease, like COPD (chronic obstructive pulmonary disease), they often cough so much that it can strain all the muscles in their upper body, which
is why you may be hurting everytime you cough. The cough often comes from mucus being too thick and difficult to cough out, so you should make sure that you are taking all your medications and inhalers/nebulizers as your health care provider prescribes. If you are really taking all your medications as ordered, and the cough and pain continues to bother you, you should return to see your health care provider, as there may be stonger or alternative medications that they can try to help quiet your cough. My other thought is that if your COPD is from smoking, then please try to stop, as this will help quiet your cough too.
Your second concern is about memory loss. You do not describe you memory loss symptoms in great detail, but you do mention it is hard for you to make decisions. If your COPD is severe, it sometimes can affect the amount of oxygenated blood getting to your brain, which can affect the way you think. I also know that many people with COPD get anxious and depressed, and start feeling overwhelmed, as it is a difficult disease to have. Perhaps all this stress on you is what is causing your memory issues. I think you should talk to your health care provider about your memory and indecisiveness, and they should test your memory, and also look into depression or anxiety as contributing to your memory problems. Good luck!