Regular Tea can have more caffeine than coffee.......
You could be caffeine intolerant.....
Tea leaves have a lot of caffeine but a cup of tea has less than half the amount of caffeine than does coffee. Also, caffeine from tea is delivered more gently and over time than the jolt caffeine from coffee delivers.
http://coffeeandteacorner.com/caffeine-in-tea-and-coffee/
All in all, there doesn’t seem to be a reason for anger to arise from tea more so than coffee.