What kind of a question is this?? Boys do NOT have periods! Ever! I agree with Knocturne, you need to see a doctor ASAP. For a boy to be 'peeing blood' is a sign of some serious problems that have nothing to do with puberty in any way shape or form. Unless you've suddenly sprouted ovaries. If you were actually listening to your teacher in health class, then you would know that only girls get periods. Ever.