Did I mess up things ?

So I'm moving in 10 days and still haven't told my mom/grandma for sure. My mom already knows I am planning to go, but I havent told her that's it's for sure. Today I told my grandma about the idea and she seemed mad at first, but eventually she said she understood my wanting to go and gave me her blessing but she hoped I would stay. I didn't tell her it was going to be soon. I guess I felt bad. I'm telling my mom tonight. My grandma also said she didn't want to let me go, which I understand I guess. Overall, Im a little dissapointed by the response. Shouldnt I be encouraged to live my life and get out there? Im 23 and a college grad. Did I mess things up by not telling her?