Birth Control Pills Question

So I started a new birth control pill last month. I was supposed to take my last active pill today. I lost one of my pills in the beginning of the pack and took another one so I don’t have today’s pill.

I went to my OB to pick up a sample pack to get the pill for today (I usually take it at 9:00 am) and they are out!

I did have unprotected sex yesterday. What’s the chances I can get pregnant?? Tomorrow would be the start of my non active pills.

I did ask them to send a script to the pharmacy but I’m just not sure it’s going to get done today.