I had both in the daycare and guess what I got an egg of an omayte. Glitch? I also had my shedninja in the day care and I got a nincada are these all glitches or what?
If it was a female Omanyte then that is normal - they are both in the same egg group so they can breed.
And if you breed Shedinja you will get Nincada because it's at the bottom of the evolution chain. You have to level it up again to get Shedinja.