Sorry so far my knees are okay, but I do have chronic pain and I have lost weight over the last few years. Find some kind of exercise that you love, I belly dance for an hour a day. The isolationist are great and you can do it in place. Anyhow, do something YOU love. I have gone from 254 at my heaviest to 168 pounds now.
How about because once in a while the tests are wrong, the results are mixed up with someone else, and they cannot always be repeated easily. There is a lot riding on these tests, do not be flip about them, really think about what you are signing up for.
If they ask you again, you might ask for Cymbalta, or its generic, if it is available, it is an antidepressant commonly used in pain management, for a decrease in pain. I call it a "two fer", lol! I cannot take this type of drug due to rare side effects, so I cannot say that it worked for me.