I recently found out that i am pregnant with my second child. Ever since then, my 2year old have been behaving very weirdly. He have been screaming and hitting me despite me trying to talk to him in a calm manner. What is happening?

You should be the one breaking the news to your child so that he knows that he have a sibling coming. Buy him a gift and tell him that it is from baby. Let him knows that baby loves him and he should too. Take it slowly and pay more attention to him so that he will still feel the love and concern from you.