Woa, really? You only drunk once? Perhaps they gave you the expresso? That's why it's bitter.

I used to love cappucino and caffe latte a lot, maybe because of the milk in there. But as of late, I didn't like it after getting my heart race all the time. The rush made me feel too alive that made me can't sleep until the middle of the night. Much worst, my heart was beating rapidly that it hurts so much.

That's why I turned to green tea. It helped me a lot as of late. I felt calmer and my heart beat would slow down.

I hope you are doing well though, I don't know much about heart palpitations as I've just learnt that recently. Perhaps you want to combine with excercises like yoga? Because I've been doing that as well for me to calm down, stress or not. But coffee is a no for me to relax from now on.