40 yr old female. change in body odor. ammonia smell when working out and after i've slept. not overweight. drink good amount of water. please help?

Many Possibilities: Since you mentioned working out I have to wonder if you have had a change in your diet, we often do not notice it, but our diet has a significant effect on out body odor. Are you on any medications now, they can also have a significant effect on body odor. With your history of lymphoma are you on steroids, could you have high sugars or steroid related diabetes. There are more, but this is a start.