Women running away

I'm having this problem like right before sex. The women are making up excuses. Like last night I picked this lady up and she seemed all eager to get with me. I took her home, had champagne and rubbers the whole works. Then when we got ready to have sex she suddenly said she had to go to the bathroom. I noticed she stayed in there for awhile so I assumed she was getting ready. After about 15 minutes she didn't come back and when I got up out of bed to go see what the deal was, she was gone. I suspect it is because I have a small penis. Does any other man have the same problem? How do you get women interested when your penis is small?