Same thing happened to my spouse. He lifts weights on a regular basis but one of his co-workers talked him into coming to a taekwondo class. He said he was feeling sick before they finished the calisthenics. It is quite easy to over do a workout.

Next time try not to push yourself quite so hard. Monitor your heart rate and do not go over 55 to 65 percent of your maximum heart rate for 2 to 3 weeks. This will help condition your heart and lungs for the added stress. (max heart rate is 220-age) Also make sure you keep yourself hydrated.