Always put a new bike through its paces before you go on a serious ride. I'll try the front and rear brakes together light-pull, individually light-pull, then medium pull then hard pull to see how the bike and I react. Brakes today exert a lot of force with the advancement in technology. That can be good but it can also come as a nasty surprise as you found out.

Front brakes can be dangerous things if not worked correctly with the back brake. Yes, the front brakes apply better leverage for braking but I don't rely on my front brake most of the time. I brake routinely with mostly my back brake. If I have to stop in a hurry I modulate the front brake while squeezing slightly harder with the front brake while increasing pressure with the back brake. If the back brake locks up the wheel it's not nearly as big a problem as the front brake locking up the front wheel.

Get back on the bike and ride. Put the brakes through their paces on dry and wet pavement. One thing that has really brought me to the ground in a hurry is if I'm applying the brakes moderately hard and hit a rut in the road. That sudden weight shift can spell disaster. Was there a slight rut or bump in the road when you went over?