we must remember that a prophecy wasn't always about the future. Prophesying can be for-telling and fourth-telling. This is a complicated and confusing issue alot of the time.
To bring it up with your pastor, i would mention to him that in Israelite conditions and law (i have been told this and i have never actually found where it says this, whether it is in historical records, or actually in the Bible. yet...) if a prophet made a prophecy about the immediate future and that prophecy didn't come true, that prophet would be stoned by the people for lying about what God told them (talk about reverence for God's word).
I can't specifically think of any prophecy that has been in the Bible that hasn't come 100% true (well... the ones that already have, yet there are still some coming). but we have to remember of the reverence the people had for God's word back then. If someone wasn't 100% honest, if someone didn't tell the 100% truth... or if someone even lied... they would be stoned. (yet then again... i am going from word of mouth... i have never actually looked this up myself. of course... i could be wrong)