I am a 64 year old woman and about two years ago I started getting a very "ugly" pain whenever I started doing anything cardio. As soon as I stopped, it subsides. This is consistent. If I walk quickly, or try to take an incline, not very tough, the moment my heart really starts to work, the pain comes.
While waiting for your Doctor's appointment, take things easy (no cardio exercise!)
If you get any more intense version of this pain, or you get associated pains any where else, like jaw, arms, chest, back, call for an ambulance to go to the ER. Do NOT drive yourself, you could be having a heart attack and you would be putting your own life and the lives of others at risk should you go into arrest at the wheel!