Do you think it was unreasonable of me to have made other plans?

I invited some old co-workers over to my new place. I asked them on Monday if Wednesday at 7 would work and only one of them responded the day of an hour before asking if it was still going to happen...now they're asking if there's something wrong with me?

I think it's kinda rude to not say anything in a group chat and then right before ask... obviously I had nothing ready and had made other plans