Hallucinating the wrong text

So a friend posted one of those maths puzzles online. Everyone was getting different answers to me, so I looked up on the original website and my answer was correct. Supposedly. I wrote on my friends post saying why everyone was wrong and today someone posts why they aren't. So I check the website again and today the answer was different, the answer everyone else had posted.
So this leaves me with wondering if the answer was changed on the website or if my brain somehow changed what I saw.
As far as I know, I don't typically hallucinate so this is all very very scary for me. I have delusions but not so much hallucinations. Could I have been so stressed at the time that my brain saw what it wanted to see?
Have others experienced things like this before?

it doesn't sound like a hallucination to me
i think everyone sometimes sees something different than what is actually because of tiredness maybe or just eyes playing a trick on you

iI wouldn't worry about it

I agree with kori.

thanks for the replies. It's okay though I wrote to them and the answer did change. I've been very stressed lately and reduced my medication by over half so I've been worried about that. Now stressing over nothing but least I know I am okay

Good luck on the reduction