When I did breed bettas (just once), they were an inexperienced couple and young. The male did let the bubblenest reduce a bit in size to begin with. If you take a magnifying glass and look from the bottom of the tank up into the nest you will see if there are any eggs in there. After all the work, I had 23 surviving fry with a waiting list of people who wanted them. So, hopefully you will have some eggs in your nest. If you don't, you can try again after resting and conditioning the pair. They'll do a better job next time.