Hi there,

I'm a 16 year old male and I don't smoke or drink. My problem, quite simply, is that after I lay down then stand up I feel dizzy, my heart beats fast, and afterwards I sometimes receive a headache.

I am relatively physically fit, I played hockey up until recently. My only thought on this was that it was due to a lack of rest, however, when summer started I began sleeping more, yet these symptoms continue.

I'd really just like to know any possible causes and what I can do about it.

Thanks a bunch.