People who met celebrities, but didn't know until after, what happened?

I was in Disneyland and looking at my phone, completely unaware of what was around me, and I body slammed into a lady by accident. To be fair, she was yelling commands to someone named Ashlee a little ways away, clearly not paying attention to what she was doing either. She looked the the stereotypical DIsneyland mom and I didn't think anything of it (fake tan, bleached blond hair, low cut tank top with booty shorts- thought she was 20 but was actually late 30's look). I apologize and move on with my life, but she gives me a stink look. In hindsight I think she was actually offended that I didn't know who she was/ didn't care. Next day I'm looking at the stupid celebrity news outlets, and I see the lady I ran into. I body slammed Jessica Simpson on her Disney day with her kids and sister.