[The Information]:
My girlfriend and I have been having sex fairly often for a little over a year now. She has been on Yaz birth control for a year and she has never missed a pill. She was late on one pill 2 days ago because we were out of town and got home late that night. She normally takes them at 10pm, this one she took at 2:30am. Tonight, she took the second pill of the third week of her pack.

[The Situation]:
We have used condoms every single time until tonight (3 hours ago). We have always wanted to know what it feels like without a condom, so after much debate, we agreed to just try it. Just to see how it feels. I wiped whatever semen or "pre-ejaculate" I saw off myself before we started. We began having sex for maybe 20-30 seconds without a condom. (It felt amazing!) I told her I had to stop and I was panicking because the idea of pregnancy at this stage in our lives is still frightening. So I pulled myself out after those 20-30 seconds, frantically and carefully used my finger to wipe out anything I got inside her that I could comfortably reach, (I did not ejaculate, but I'm sure I'd be a fool to think I did not get anything inside her), wiped my hands off on the sheets, and put a condom on. We finished having sex after that. The condom did not break.

[The Question]:
I'm a worrier. I've been reading miscellaneous forums for an hour now, and I'm reading that a lot of girls allow their partner to ejaculate inside them completely while they are on birth control pills. I know that the pills are not 100% effective and I know that there is always a chance; even with 2 forms of birth control there is a chance. But what I'm asking for is an opinion. If you can piece together the information with this situation and put yourself in it, answer me this... in your opinion, with regard to pregnancy, are we safe?

She keeps telling me that she's sure we're okay. I trust her confidence to an extent, but I'm the type that needs an outside, second opinion on matters such as this.

Also, if you truly feel that I need to be worried, what is the next correct thing to do in order to ensure our safety against pregnancy?

Your honesty will be greatly appreciated.
If I left out any information that would be helpful, please let me know.

[Additional Information]:
While it did feel amazing, this has been too much for my worrying mind, and I've promised her that it's absolutely not a letdown to go back to our usual routine of using condoms every time. As long as I've got a fresh, ribbed condom, and she's happy and comfortable, I'm in heaven while we're having sex.

*Forgive me for the lengthy post, I'm rather long-winded and highly detail oriented. Didn't want to leave anything out.*