Caught in a Moment of Weakness

I've been so focused on my studies and getting through grad school that I haven't really dated or even thought about sex much lately. But last week, after a particularly stressful day, I found myself at this new bar near campus, drinking more than I usually do. Before I knew it, there was this girl, let's call her Sarah, who started talking to me, and next thing you know, we were back at my place with the intention of studying together. But things took an unexpected turn. We ended up... well, let’s just say she convinced me that tonight was about pleasure and not productivity. It felt so out-of-character for both of us, but it happened. Is this something everyone deals with or am I the only one who feels guilty about losing control like that?