Hip pain can come from many different things. Probably the most common cause in triathletes is ITB related; ITB pain doesnt necessarily have to come in your knee. That will not be a deep pain though. It's pretty much impossible to make a diagnosis here (err, well, not that _I_ could make a diagnosis in person either
). Do you any stretching on your hip flexors and glutes? If not, it is well worth doing, along with using a foam roller on your ITB. You do have a foam roller don't you??
They are cheap and well worth it.