What Causes Shortness Of Breath, Chest Discomfort And Fatigue?

Question : Hello,
I have a very stressful job and an even more stressful home life. I recently had an EKG that was not normal, twice over a period of three weeks. The EKG showed a change in my "something". I saw a cardologist and he gave me nitro's and said he was going on vacation and would do a chemical stress test when he returned. I am very out of breath when I talk after walking 10 ft. I get out of breath when getting dressed, also. I did have an espisode a month where I could not get out of bed for two days, had chest pain, Nausea and vomiting, and was sweating with out a fever. I have since had episodes every two or three day with overwhelming fatigue with some neck, elbow and cheast discomfort. I have been taking at least 2 nitro's and things ease.

My question is should I go to ER if I continue to have these episodes or wait for the cardiologist to get back. I have not thrown up since the first episode. I tell myself that if I don't get nauseated enough to throw up then I shouldn't go?

Please advise?