Try eating a little bit and then walk around a lot. Eventually your Sim's Sanity diamond will decrease to the point where you fail in chatting, flirting, or imitating against another person. In the house you bought, go into the music room so a ghost scares you, making your Sanity diamond decrease. Afterwards, after your diamond is all the way decreased, your Sim will fall on the floor and feel strange, which will make you start from your new house. You will be thrown over the fence of your house, but will feel better afterwards. It will take 500 Simoleons to get you back on your feet, and you will lose all your Sanity points.