What Are The Chances Of Pregnancy Through Outer Course?

I am a bit concerned about the possibilty that I could be pregnant. My boyfriend was over at my house two days ago and had an erection. I didn t do anything with it. I asked him if he wanted to take care of it in the bathroom and he did. He washed his hands afterwards, but I don t know if anything could have gotten onto my hands during the remainder of his visit. I never touched him, just his hands, and I never felt anything wet. I am concerned because I went to the bathroom before cleaning off the toilet completely, even though there was nothing visible on it. Is there a possibility that, in this process, any sperm could have come into contact with my vagina and made me pregnant?