Emily, DON'T CALL HIM.

What I've noticed with my own H (and in other people's situations here) is that when some small progress is made, the WAS will sometimes distance themselves again. Maybe that's a defense mechanism, I don't know. But it seems to be the way these things go. Perhaps he is overwhelmed with his feelings for you and the kids right now, and confused about his (former?) feelings for the OW. You have to give him some time to figure these things out. Back off and let the man have some space!