I Don't Love You

My son is a six year old kid who cannot express himself well. Last Friday he was suppose to have a new year celebration in school. It was my mistake to choose a shirt that he does not like. I thought he might change his opinion this time. Boy was i wrong! He started throwing tantrum and would not even wear any shirt when i asked him to choose another one. See how stubborn he can be?! The school bus was almost here and he refused to tell me if he wanted to go to school. I was so angry that I beat him up. I knew I should not have vented my anger on him but the bomb in my head just exploded uncontrollably.
"I don't love you!" he cried out loud. I was too shock for words. I felt a hammer slamming down hard in my heart. Every night , we will say "I love you" to each other before he sleeps, but never has he said " I don't love you" by himself. He must be feeling very upset at that moment to be able to say that. I felt really upset too although ironically I felt happy that he was able to express his feelings.
That day he was half naked and refused to eat until five. I gave him milk in his bottle and left him alone. Minutes later, he came out of his room, and threw up the milk. Then I realised that his refusal to wear a shirt could be due to his illness. ( or could it be starving for too long?). I felt really sorry for what I have done in the morning. That night, when I told him I love him, he told me sickily and wearily that he loves me too. There was a lump in my throat and tears in my eyes.
My son is autistic.