.....Ferretguy (Dwarf Barbarian)
You've misunderstood the standard point buy system (so did I, until recently). As per the DMG, page 169, you pay one point per increase until you reach 14. 15 and 16 cost 2 points each. 17 and 18 cost 3 points each. As is, you have too many!
Ranger Rick (Dwarf Fighter)
You've made the same mistake as Ferretguy.
.....Incidentally, for this particular campaign, you are NOT required to submit a backstory, as that gets into the whole acquisition of personal information stuff. However, you may if you so desire, and it may actually have an effect. An example of a particularly relevant background would be, for example, membership in the armed forces; since the real world IS actually in danger here, soldiers of all sorts are being strongly encouraged to volunteer for this (they aren't being ordered as of yet, though), and governments are of the opinion that any civilian volunteers will be acting under military personell, once through the Portal. Not that this will neccessarily happen, it's just the general assumption, fueled largely by the fact that the governments don't yet realize that this will be quite unlike any previous military operation.