Had too much caffeine and now feeling like crap?

I don't usually drink coffee daily, but I work half-time in a cafe and today me and some of my coworkers went to a coffee course, where we learned how to make espressos, cappuccinos, lattes etc. We practised many times and mostly drank all the drinks we created. All in all, I had like 2 espressos, 6 cappuccinos and a latte. After the course ended, I felt buzzing at first, then my hands started shaking, then I got really hyper and overenergized and an hour later needed to go to the toilet all the time and I felt really sick to my stomach. I'm not going to drink any more coffee anytime soon, but what I did today, can this be harmful in the long term?