Bacterial infections-bleeding-pregnant-HELP!

So I'm 29 weeks. Everything so far has been perfectly fine and healthy. At 27 weeks after complaining enough about discomfort I was tested positive for a uti..a yeast infection..and ureaplasma(overgrown bacteria linked to preterm labor & birth) I was given multiple antibiotics to treat infections. My systems subsided a lot and I was feeling better about things. But now within the last week I have spotted fresh blood on two separate occasions 4 days apart. The first time I bled I went immediately to my obgyn who checked my cervix..which was closed. I'm in a lot of cramping pain down there. My doctor wouldn't give me an ultrasound to check my plascenta because she said " it was fine at your 20 week scan" She said since I'm carrying very very low the pain and pressure is normal.

Like the fresh blood came from somewhere right?? Should I stop worrying and tell myself I'm a paranoid ftm or should I go see a different doctor? Any advice or personal experience would be highly appreciated please!!