Yep, I've had this happen to me before unfortunately. It's actually been my only fight so far.
Some girl I had known since high school had been after my boyfriend and I ended up accepting her challenge to fight for him.
I was a little nervous due to the stakes, but in my mind I thought I would wipe the floor with her. She was one of those prissy/popular girls in high school. The cheerleader type, which she actually was a cheerleader. She got tons of attention from the guys and was always supper annoying, loud, and obnoxious. Basically, she was popular and she knew it, and she was a complete bitch about it.
I thought I could take her easily. After all cheerleaders cant fight, right? They're not athletic, they just sit on the sidelines and show off their bodies.
Well, let me tell you when it came down to the actual fights I was in for the surprise of my life.
We did a format where it was boxing/wrestling/catfighting each day for a maximum of 3 days. Best 2/3 fights would win the day and 2/3 days would win the weekend. Let me just say that she never let it get to the third day... as a matter of fact she never let it get to the third fight. She easily 2-0'd me both days. On the first day she absolutely dismantled me in boxing, knocking me out. Then she pummeled me badly in the catfight later that day, scoring a second knockout.
I didn't fair much better on day 2. She quickly pinned me in wrestling, and then went on to absolutely destroy everything that was left of me and my pride in the boxing match, knocking me out for a third time...
The whole ordeal was the most painful/embarrassing thing I've ever been through in my life and I've been afraid to fight since, despite taking some self defense classes.
Lesson learned, watch out for those cheerleaders! They can sure pack a punch... I found out the hard way who was the better woman in everyway. : (