Why am i afraid to be seen by my dad hanging out with male friends?

We were hanging out at the mall with 2 of my male friends, simply friends, I saw my dad in the same place we're going. I bid goodbye to my friends and ran off in just a split second. I don't have a boyfriend. I had once but my dad never knew it. We are not so close with my dad. I just feel afraid he might think i am doing or fooling around and i don't want him to think that. Is this normal? I don't know how to explain to my friends why am i ran off just bec. of my fear of dad. What should i do?