hello, I was having my 30 minute tennis lesson, almost got to the end and suddenly I could not breathe properly. I really struggled to get my breathe back. i had to stop. luckily there was a nurse at the court and she encouraged me to breathe in through my nose and exhale through my mouth. i am 49 years old, female, am going through a pretty awful divorce but have been getting myself fit over the last 2 months and was feeling ok. I have been tired over the last week though. what was this shortness of breathe all about. I feel very tired now, and have gone to bed to rest. could you tell me what is happening. thanks