The first colon doesn't make any sense: a colon must be preceded by an independent clause. "There's" should be "there are" because you are talking about something that is plural. I will submit corrections accordingly.

Here is the original quote so people can see what I'm talking about:

"Not to be a downer, but when you think about it: there's a lot of things that can kill someone. Anything from car crashes to contracting cancer from hotdogs. You could die from stressing out over how many ways you can die. And with all those ways to die, the best thing to do is enjoy life. Really appreciate what is good. I think I realized what many people have been saying for years: life is short."