It's too late to use now, but you could have had her take the morning after pill(Plan B or Next Choice). You made a risky choice by having unprotected sex, without a condom and now have to deal with the consequences of your actions. If her period is late, have her take a home pregnancy test first thing in the morning. If the test is negative, use this as a learning lesson to never do again. If she is pregnant, then you both need to discuss what to do.
If you don't use protection (condom or consistent birth control (every day and around the same time) then you do have preejaculation and yes you can become pregnant.
Yes because missing birth control is like not even taking it. It has to be taking as directed or it's worthless. Pulling out also does nothing and shouldn't be relied on to prevent pregnancy. Pre-ejaculation is still ejaculation and contains sperm. You don't honestly have too many options. I personally feel if you're enough of an adult to engage in a reproductive act, you are enough of an adult to take care of that product, which would be the child. Then there's also abortion and adoption. First thing first would be to wait two weeks and have her take a pregnancy test with first morning urine. Unless you're wanting to get her pregnant, you need to be using condoms at all times, and she needs to start properly taking her birth control. If she's not going to remember to take them everyday as directed or doesn't care enough to, she needs to get on something else. If you don't have the proper protection--abstain until you do.