Caught Off Guard

I'm a retail worker at this big chain store, been there for about three years now. The past couple months, I've started dating casually but nothing exclusive yet. My latest date was this guy named Alex; we hit it off pretty well and decided to go on another date soon. So yesterday we met up at this bar that's popular with our age group - mid-twenties to early thirties. We had a couple drinks, talked about work stuff, movies, everything you'd expect from the beginning stages of a relationship. But as the night went on and the alcohol flowed, Alex got more playful and flirtatious. We ended up back at my place that night. Now here's where it gets tricky: I initiated making out pretty eagerly because... well, let's just say I've had a crush on him for weeks but was too shy to act on it until last week. But after some heavy petting and foreplay, when Alex went down on me, things got weird. I felt guilty right away - Alex seemed to think it would lead to more than what I was comfortable giving that night. We had been clear we weren't in a relationship yet, but my actions made him assume otherwise. When he pulled back and asked if everything was okay, I panicked and said yes even though I wasn't sure at all. I've replayed the night over and over since then, feeling awful about how confusing it must have been for Alex and worried that we'll never be able to move past this awkwardness. I don't know what to do - whether to confront him right away or give some space before bringing up my true feelings. Part of me feels like a real asshole, but another part is still struggling with wanting more than just casual dating.