<human>: I don't want to be too specific because it's a little embarrassing, but I think today I confirmed I have an irrational fear of a very very specific (and very very rare) injury. 

Several years ago, I was reading a book and this injury came up. I passed out while reading.

About 3 years ago, I was at home dozing off. The thought of this injury passed through my head, and I couldn't stop thinking of it. I passed out again and hit my head (and got a big welt).

I honestly didn't connect the two incidents and didn't think much of them: I thought "wow, that's some good writing" in the first case, and "wow, that was weird" in the second case.

But just now, I nearly passed out in public when a comedian happened to mention this specific injury on stage. I started to get dizzy, I sweat profusely, and I felt myself going black. I held it together and didn't actually black out, but it took a good 20 minutes to fully recover.

Just to clarify, this isn't something that would likely actually happen to me. It's not even that serious of an injury, and it's rare enough that it's only mentioned in passing occasionally. Again, it's clearly very irrational.

So anyway, what now? Is there something I can do to keep this from happening again? Is this serious enough that I should talk to a psychologist? I'm a bit worried now, as I got injured because of it once, and now I nearly caused an incident in public.

Can you summarize the given text in a few sentences?
<bot>: I passed out twice in private and nearly passed out again in public because my body seems to freak out at the thought of one very specific kind of injury. What should I do?