I know you said you saw a cardiologist and had a stress test (ecg?) done but what about an echocardiogram? All my ecgs and monitors came back normal but the problem was quite visible on an echo. It's not a good idea to play around with what might be right if the cause is not certain.
I'm quite surprised, I have had many meals from Simply Asia's all around, Somerset Mall a few times, Marine Circle a few times and West Coast Village and I've always had a nice experience. I found that their Thai green curry is far better than any other place I've been to.