You can't depend on the word of someone that they are using birth control. You just have to use a condom, or alternatively wait until you are in a really good, trusting relationship. This could have been a close call, imagine if she really was preg? Not a good situation for all involved.
At last, someone brought this up! Unless you are prepared to be a father, you should be using condoms to protect yourself (not only from STDS, but from an unwanted pregnancy).

hope all gets sorted soon, and you both get your lives sorted.

k