Is This Correlation Causation?

So I was recently diagnosed with ADHD and today was my first day on concerta (27mg). Afterward taking my first dose I felt very hyper, fixated on things, and had lots of anxiety. Is this a side effect or was I just feeling anxious today? I am an anxious person in general but this felt like a lot. I still am feeling a lot of these symptoms right now and feel like I’m not in the best place of mind.