You can't get yourself off, at least not before she takes control, leaving you at her whims while all you've done is allow her to recover and push yourself closer to a stronger orgasm that you may very well not be in control of...
You're just about to start fucking her when you notice that she's still got her bra on. Time to use that to your advantage, gripping on it and using it for leverage to fuck her that little bit harder.
In quite the show of strength and dominance, you not only manage to sweep her off her feet, but also hold her upside-down in a standing 69. This gives you freedom between her legs while she has to choose between working between yours or trying to escape.