Toddler tantrums can never be stopped with you also raising your voice. First step starts with parents. Calm down. Second, tell your toddler that raising voice doesn't make him/her get what he/she want. Explain that shouting isn't a good way to ask for things and if your kid shouts more, tell that he/she won't be getting the stuff until the shouting has stopped.
To get a more detailed info on what to do when your toddler screams, check this link: http://www.whattoexpect.com/toddler/behavior/screaming-and-screeching.aspx