First time

For the first time in 13 years of being together- we didn't use protection or pull out and pray :) of course I was ovulating. Why am I scared? I adore my husband so much- and he is totally ok with this. Until three days ago we never really had the "talk". I am 38. Should I go for the gold and do it again tonight :) what are the chances of getting Prego on the first try?
Nervous but excited!  Thanks y'all!