Okay.. now here is my 4:36 am. Im drunk just got home from the casino and blew a G bar and kinda pissed but trying to be helpful response.
Males are just like females in the sense that they try and lubricate the vagina. Males secrete what is called pre-cum as our help to the lubrication process naturally. Pre-cum has a VERY small amount of seaman, considering the amount of pre-cum is also very minimal. However its like baby rattle snakes venom, there might not be very much but its twice as potent.
With that said, the pull out method is the only form of "natural" birth control recognized by the catholic faith. The idea is to have sex when she is in between ovulations when she is the least fertile.
If you pulled out and didn't get greedy and send a single pearl from the necklace into her, and she isn't just getting done with her menstrual cycle, chances are... you will be just fine.
If you are still stressing it tomorrow ,talk to her about the idea of the day after pill. Its most effective within 48 hours so you have some time to decide if you want to drop the 65 bones for a forced period. If you do go that route and next month she's "late" just remember the morning after pill is like a nuclear bomb for the females cycle and it could take several weeks to get back to a "normal" cycle.