“I have to fast again tomorrow?! ;P’
That would depend why you’re fasting. Are you fasting because of the creation of the state or because of the fact that there are Yidden who think it’s a cause for celebration?
Personally, if I were to fast, it would be because of the Israeli flag hanging two feet away from me that is making me nautious. But then I’d have to fast straight through Yom Yerushalayim, so I think I’ll pass.