Feeling Drained After A Date?

I'm not sure how else to explain this, but I went on a casual lunch date today and now I feel like I've been hit by a f-ing truck. I had a pretty good time, but the whole ordeal has left me feeling absolutely drained. Has anyone else experienced this? Is this, like, normal???

For context: I'm female, late 20s, have had a bf before but have never really dated around. Diagnosed with ADHD later in life (so definitely ND), but reflecting on my social life and habits makes me think I have a bit of the 'tism too. This isn't the first time my energy has crashed post-socialization.