Around 17 weeks i was told i had Placenta Previa with my first, by 37 weeks it moved. So don't stress you still have plenty of time for it to move.
I was told I had placenta previa at my anatomy scan also. They didn't know if it was partial or complete I went this past Friday 32+5 and it was confirmed that it had moved up . You still have a lot of time for it to move up so I wouldn't worry if I were you, easier said then done , I know. I went to googling and totally scared myself. Hope you hear good news at your next ultrasound !