What Causes Excessive Weight Gain With Pain In Arms And Legs?

Hi. My name is Toni. I am a 53 year old caucasion female. I have a dull pain in both arms and in my legs. I have recently been diagnosed with COPD. I have gained about 40 pounds recently without changing my diet or lifestyle. I have had memory issues for a while. I just don t feel good. Any suggestions? Thank you.