Concerta XL 18mg, very spaced out

Hi everyone! Just had my first dose of Concerta XL 18mg today and it's been very odd. I had a coffee about an hour after my dose as I didn't want caffeine withdrawal symptoms to conflict with the Concerta. The coffee + Concerta made me extremely jittery and anxious, but after that went away I've spent the rest of today just feeling incredibly spaced out. I feel like I've probably spent close to 1/3 of today just staring into space or staring at videos playing in front of me. Been trying to clean up around my flat for a party later, I can go for bouts of about 20 min before I end up crashing on my sofa.

Read a lot online about people experiencing this effect (albeit on higher dosages), but is it something that indicates I should stop taking it until I speak to my psychiatrist, or is it temporary? I've emailed my psychiatrist, but I don't expect to hear back until Monday at the earliest.