One day I experienced the same thing. The worst cramps. My guess would be that there is blockage. And pushing that blockage through can be painful especially if it's old crud stuck to your insides. Almost like child labor. A child's head is painful. That's what I can compare the cramping to. The feeling is the same. (Child labor is much more intense) We probably have old crud the size of child's head that is being forced out with the combination of the lemon juice and the tea.
I'm not trying to scare you and this is just a guess.