My friend... You absolutely have GOT to stop fearing this brain eating amoeba. I've read many of your past posts, replied to some too. They have totally irrational, and believe me - as I've told you before - I've had this fear! I've been there! But I now recognize how completely irrational I was being. You need to do the same.
Are you never going to swim again? Take a shower? Dust your room? Don't let this fear still another second of your life. Just drop it, I promise you you'll be happier. It is so incredibly rare to be infected by this in the first place, but if you were, as I'm sure you know because you probably googled every single thing about it, you couldn't do anything about it anyways! So what's the worry for? Don't worry about what you cannot control. We all do it, but we need to learn not to.