With how hot the sun is, and all its radiation.
I'm surprised it doesn't give me the same heartburn that you do.
This could possibly be considered a medical condition, but I'm sure no doctor would be able to properly diagnose me.
Although, it appears to be a problem of the heart, the symptom is clearly not medical because, it only occurs when I find myself thinking about you.
I'm not sure I want to be cured though, that would mean losing what makes my heart beat...