I didnt cycle my fish tank?

Its great they they are in a 10 gallon with a filter instead of a bowl. With betta's, you should not have to feed them much, maybe once a day to every other day. Feeding less will help keep the bioload down until your tank is cycled. If you want you can test for ammonia, nitrites, and nitrates to see how your cycle is coming along. However your best bet is to just do small frequent water changes. 1 gallon water changes twice a week, maybe even 2 gallon water changes once a week until you know how the cycle is coming along. Bettas dont have a very big bioload in the first place so just make sure you dont overfeed and your bettas will be very happy and healthy. If your bettas start to flare up at each other through the divider you may want to consider exchanging one of the males for a female.