Handphone Bills

Its another day where SingTel send the bills to my home. Maybe due to bad mood, my Dad suddenly scolded me on my handphone bills. What can I say, I have my rights to remain silent.
Here is why he scolded me, my HP bills was over $30, this include the plan fees, that means the other fees was about $12. Because of that $12 he questioned me and scolded me for the whole night. $12 is the calling and sms fees, I already told him the reasons that may lead to the increase or maybe they got errors. Then dunno whats wrong with him, he suddenly mention about the last plan we had and he say that is was not that high compare as last time. WTH I remembered clearly it is also $30++, now also $30++ but he scold me. He also want me to pay the bills myself, what is wrong with him? Then he start cursing the student plan I had, again I was like WTH, I had that plan for about 4-5months, the bills is always constant but now he scold me.
Because of that $12 I cannot sleep well the whole night, confused and irritated. $12 can made him scold me, I bet $100 he can disown me. $12 per month, what can u do with that, buy 2 more bottles of beers?
People say Singapore parent over dotes their children. How come mine does not, instead creating more troubles and worries for me?