Calm down sweetie. It's a really really good chance that you are NOT pregnant. I think you are simply stressed, which is why you should take a pregnancy test. You are probably not pregnant, but it will ease your mind and you will stop stressing.
The majority of the wetness could've came from you. All women are different, some women produce alot of vaginal fluid during sexual activity, and some women produce very little. While it is possible to get pregnant through dry humping, I don't think it's very common.
First off get tested just to clear your head. If you are pregnant, which I highly doubt, knowing early is the best thing for you.
Second, the next time you do something like that with your bf make sure you guys use some kind of protection. Even though it isn't common to get pregnant this way it is possible, so be more careful next time. Try and relax and I hope this helps you.