Sorry, but that isn't possible at all. I would go to the hospital if I were you, since your heart would be one the wrong place then, lol.
Er, that is possible. You can see the skin vibrating just to correct you. And no I'm not trying to be 'smart' or whatever but I happen to be on a medical/nursery college and I can tell you that you can see it, same for the stomach vibrations.
Stomach vibrations are possible for sure, I never denied that. But being able to see your heart pumping shouldn't be. It is only possible if your heart would be on the wrong place aka closer to the skin than it's supposed to be. Also, I plan on becoming a nurse, so you're not alone. EDIT: I decided to use some magical google shizzle. And it would most likely be possible if you're pretty skinny or 'thin', weird thing is, I'm really skinny (I'm way under the weight that I should have, so that's bad ofc) and I can't see it at all. Oh, and if people would also hear it beating (not that others can hear it if they get close to your chest, but if you can hear it by yourself/ in your own head), then you should really check it out. Since that's not really normal. Some people have even been experiencing pain because of this all, so yeah, anyone who has this might wanna check it out. xD I was just saying that it shouldn't be possible, not that it's impossible.
I hear my heart beating in my head, but only if it's going really fast or I'm blushing or I'm in trouble (I am really overprotective about getting in trouble by a teacher or adult)
Same and it's nothing to worry about. Our arteries and veins are all leading out of the heart to every single body part, including the brain or 'the head'. The heart pushes the blood (which creates a puls) in the arteries and you can feel the puls as a 'beat of the heart'. So if you can hear it that only means that your arteries might be closer to your auditory system or that your auditory system is very good.
If you're hearing it for no reason, check it out. But after a work out or blushing etc, don't worry. Everyone has that probably (it's annoying af for me xD)