A childhood belief about church

I went to a Catholic school and when the teachers talked about communion they told us it was "the body and blood of Jesus Christ"...I pictured Jesus in heaven (heaven located on the clouds of course) with a cheese grater (the kind that gives u slices of cheese) carving off peices of his skin for us to eat. For the wine i pictured him cutting his arm and bleeding into a cup.... I thought this was true for years...