Do I have oral herpes?

I've recently being worrying about whether or not I have oral herpes. I 'm a girl, and I had oral sex a week and 4 days ago. I have had oral sex with this guy two other times before. My lymph nodes are sorta tender and I have a few white bumps on the inside of my gums. I haven't had a blister on my mouth or anything. Am I worrying over nothing, or should I get it checked out?