Caught in the Moment ...

I never thought I'd do something like this again after dropping out of grad school and settling into marriage. Last week, though, at a small party where everyone knew each other's spouses... she was there with her husband but I couldn't help myself. We ended up in an empty room for what felt like hours, lost in the most intense sex I've had in years. Her breasts were pressed against me as we moved together, our moans filling the space... Afterward, all I could think about was how it made my heart race just thinking of doing it again behind everyone's backs. Is this normal? What should I do now? ...