Since you checked preflop, you were following the "no set, no bet" plan, right? Then you didn't get the set, and there are overcards... so why'd you break plan?

If you thought she was playing too many, then a preflop raise could have been interpreted as a blind-move, narrowed the field, and given you the potential to go after the pot with a continuation bet.

Instead, you checked the flop and so didn't know if she was just pushing you around. If she's playing a lot of hands, she might be going A3s or something and actually thinks she's ahead.

anyway, my first impressions...