I think, however, the OP's fantasies sounded as though they were intrusive in her head. It did not seem clear (at least to me) that she was confident that they would stay purely as fantasies - there seemed a wobbly haphazard 'I wanna actually do this' quality right there.

I am relieved that the urges have passed for you, OP. You do need your medication reviewed though. I know you are suffering but that still doesn't absolve you of blame if you seriously think you might hurt your children. Over a bloody xbox. Ffs.