You know it's so difficult to answer you because each of us are different due to sperm counts and the like.. as well as where you were at, ie) ovulation time or not.
It's always going to be risky "gambling" and that's what you did...
See what happens when we don't have sex for so long and the opportunity arises
I'm sure you'll be fine.
But, pull out at least next time, tell him at least if you didn't and maybe always from now on carry a condom just in-case... Then if you ever do this again you've got a few methods of protection as best as you can.
CW