if you look at the first picture you also notice that the leaves arent really connected where they come togeher there is a longer stem that leads the middle leaf further out, definitely not marijuana, there are many wild plants that look like reefer so this is probly just a cool coincedence that it is growing where you dump your seeds. marijuana leaves always come together at pretty much the same point on the stem. i found a similar plant to that in my friends yard once and really thought it was weed too... until i noticed taht it had these little sticker things on it and that the branchers were not directly across from each other as it was growing. some marijuana doesnt have leaves directly across from each other but i believe its only during flowering.