Shaking syndrome is something that occurs after you send a risky text , or receive a text that makes you nervous. The symptoms are severe shaking and shivering that lasts for a long time.
From the game "Shake it up" on Mario Party 8 for the Wii, in which a player must shake his/her can for 5 seconds and whoever has the highest stream wins. Naturally, this became a great innuendo for jerking off.
Expression for obsession of a certain thing; often used sarcastically. "Shaking and Crying" comes from hardcore fans, who tend to 'shake and cry' when they affected by their fandom.