What Causes Bleeding During Ejaculation?

hi I have a question. My fiancé has blood that comes out when he ejaculates...at first I thought it was me but its not...its happened before very little but like I said I thought it was me so I didn't worry too much. He claims hes been fighting a track infection. He had one about a month ago so he says and they gave him a shot and did some blood work and stuff and he got better...but then a few weeks back same thing happened. he said he had discharge coming from his penis it hurt when he peed and he couldn't even masterbate because he said it hurt to even touch it. So he went back to the drs and they said he just had another track infection. Im starting to believe its something else...especially since blood came out mixed with his cum when he ejaculated, and hes not telling me. What else could it be? And should I be worried?