What Causes Recurring Facial Flushing

Hi there, I am 24 years old. I seem to be having a bad flushing problem. At first i thought it was blushing but then when my friend saw my whole face very red, he told me that it is actually flushing. But i feel hot when i flush. and i realize that my whole face turn very red. As i am fair it is very embarrassing.

I do blush because i am shy but sometimes im driving alone in the car & my face just light up. It very embarrassing that i flush at certain people & when im shy or when im doing almost anything. I give wrong signals to alot of guys as well.

Is there anything i can do? is there any medication that i can take? or do i need a body check up to find out whats wrong with me.