The mushroom is a fungus and comes from the potting soil. Mushrooms grow where there is decaying matter and won't hurt your plant. You can remove it, but wash your hands after you remove it just in case it's not 'friendly'.
Also, please remove your caps lock on your keyboard. In computer language it means you are yelling and it's hard on the eyes.
When weeding, the best way to make sure you are removing a weed and not a valuable plant is to pull on it. If it comes out of the ground easily, it is a valuable plant.