yup definitively snail eggs.. IMO take them out! they multiply FAST and lay eggs everywhere so you will have more snails soon
my experience with snails, never bought any but ended up taking some home on some live plants that i bought from my LFS.. within 2-3 months i had literally over 150+ of them of all different sizes. i was literally siphoning them out 2x a week to keep the population under control in a 10g tank.. i ended up moving the betta that live in the tank to a new tank and i threw away EVERYTHING from the snail tank, tank, gravel, ornaments, filter. just to be free and clear of snails. there are better ways to get rid of them if you end up with more than you want.
just let us know if you want suggestions