it might just be spring fever. One horse at the stables where I board got crazy once the warm weather started coming. He's go into "rodeo" mode (as we all called it). He wouldn't stop, would try to rear or buck when you made him stop, and would just want to go fast all the time.
How does she act in the stall? Is she still misbehaving, or does she behave fine?
Try, when leading her places, to turn her in a tight circle if she misbehaves. Most horses don't enjoy going in tight circles, so she hopefully would realize that if she stops misbehaving, the circles will stop.
How long have you had her?
How did she act when winter was starting?
If you've had her over a year, how was she last spring?