theres no way of knowing if its cycled unless you do a water test...
water from your cycled tank doesnt really help much since the bacteria doesnt live in the water (some does) but instead on the surfaces within the tank. and if it only sat for 2 weeks, then it did not have time to cycle.. that usually takes 4-6 weeks. so you didnt really do what you are "supposed" to do, b/c you did put the fish in a non cycled tank.
do you have a water test kit? if not, then go out and get the master test kit from you lfs
.. (my petsmart has them for $20 so its not a bad deal)
and i havent tried to breed bettas but i have read that sometimes the female will try and kill the male instead of the other way around as one would think. i heard that a good way of introducing them is to have a divider in the tank, and then take it out once the male has built his bubble nest... but like i said i havent bred bettas its just what i have read.