anxiety help?

so about a week ago I got super sick when I was home alone to the point I thought I was going to die. my parents rushed home to take me to the hospital. since then i’ve been having these thoughts nonstop about how i’m gonna get old and i’m going to die one day and I don’t know how to stop it. i’m turning 19 in a month and I just feel like I don’t have enough time for everything before I go. any opinions on what to do?