I just started running about 14 weeks ago. I'm 26, 27 in October. I just ran my first half marathon (13.1 miles), and I'm aiming to run 30 miles when I turn 3

I just started running about 14 weeks ago. I'm 26, 27 in October. I just ran my first half marathon (13.1 miles), and I'm aiming to run 30 miles when I turn 30. I'd like to do it in a respectable time too.