Hardest Sleepover plan

Now on the left if you look down you will see a post on my twitter saying "Cant Wait in two weeks cause my friends are coming over for a sleepover" Yea well yesterday a girl who i invited right after i asked them about songs they like on facebook to hear she wall posted on the event about how her and the other two guest i invited had a choir concert that day but a few days before that she said she had a date with her boyfriend (F.Y.I she is probably making that up) So anyways i asked one of her friends if they had a choir concert. She said "Oh crap we do" So i said no prob and i changed the event to friday. Then a few secs later the girl i talked about how they also have one friday too. So i turned off the computer and went over to my mom and just cried. There was no way to have a sleepover.. But my mom said to look up.. The next two weeks was May 7th, First i said no cause it was mother day weekend. But then i agreed. So now it will be much easier to plan.. But lets see what happens next..