Forgive my stupidity...
Is your plant a Saururus cernuus ? I thought this was a bog plant or water garden plant and not something to be grown in a pot indoors.
Around here the plant grows in roadside ditches and is quite beautiful - I have always wanted to dig some up and bring them home.
Yes, I see the trails on the soil surface. Maybe the snails and/or slugs arrived with the plant as an unintended "gift" from the seller.
