I've experienced that strong heart beat whenever I just relax. I have for decades. It doesn't speed up. I never thought anything of it except maybe neet. If I lie on the bed and relax I can even feel the bed rock with the beating of my heart.
I've never experienced astral projection.
I've only recently gotten into meditation and Qigong. I've not associated this with either of those experiences. For me it just comes with being still and relaxed, but not any obvious mental state change.
You are perfection.
Iam2 
