Hi Sangria,
I also had a low lying placenta and just took it a bit easier, like I didn't do any heavy lifting. I was just really careful. I now have a lovely almost 2 month old baby boy. There is still time for it to move, my Gynae just said that she will monitor it and i should go and see her if I had any concerns like if there was bleeding. But you should be find and it is nothing to stress about. Just relax and take it easy. Babies don't like it when we stress.
Good luck with your wonderful journey, enjoy every moment of it.