I put a thumb tack in my mothers favorite seat
Why would you put a thumb tack on her seat? Are you trying to cause her pain?
I did it because I wanted her to get the hell out of my house. She made my life hell.
You did something that could physically hurt your mother. There are other ways to ask her to leave without harming her.
She's a big bitch and an evil person.
She will quickly figure out that you played a prank on her. Once she does she will likely punish you and make things even worse. If you don't want your mother around just ask her to leave and to never visit instead of beating around the bush with pranks.