Continuity mistake: Before Tom is about to draw a line on the alarm clock on the blueprint, you can see on the left hand side of the clock there is an "A" and an arrow, and on the right hand side is some writing. When Tom draws the line, the "A", arrow and writing have all disappeared.
Continuity mistake: When Tom finishes drawing up the blueprint, the stand with the pot and cup on changes position between shots.
Continuity mistake: When Tom finishes drawing up the blueprint, he draws a mouse and writes the word "Mouse" underneath it. When the blueprint comes to life after Tom lies down on the bed, the word "Mouse" is now underlined.