How do I know if someone else's signature is written by myself?
First of all, it depends on whether the other person is a haggle over every ounce. If so, what he (she) wrote can be related to you or what happened between you recently, and what he (she) wrote is most likely aimed at you. If not, then you'd better not worry too much. After all, you know each other, and acquaintance is a kind of fate.