Li Min /China Daily

Ripping off my Jason Voorhees facemask, I sucked in the parched fumes that pass for oxygen in my office and stared balefully at the chocolate love hearts that were chemically bonding to my desk.

"They're for Valentine's Day," said a female colleague.

Amid all the particulate matter and leftover newspaper ink, the confectionaries had already cultured into new bacterial super-agents. There was nothing romantic about them. I wondered if anyone had a spare spatula or petri dish lying around.

I wanted to say, "But Valentine's Day was over a month ago, and besides you're married." Turns out the chocolates were from another female colleague. She's also hitched. The question is: Was she secretly in love with me as well?

Unholstering my battered Galaxy 2, I scrolled back in time to Feb 14 to review a dozen "Merry Valentine's Day" messages from other happily married women and straight male friends, mostly accompanied by animations of raining binary code.

In China, confusing social codes abound. Best you can do is hope to avoid committing social suicide along the way, or worse.

I fell into a bigger cultural trap a few months earlier by forgetting to book my ticket out of Shanghai when it sees the world's biggest human migration - not of Chinese returning home for the Spring Festival, but of expats bailing out over Christmas.

Canny laowai figured out long ago that heathens overrun the city at this magical time, burning crosses, looting churches and drinking goats' blood. The only gift you're likely to get is that some old lady might not steal your taxi when you're hung-over and late for work on Christmas Day. But don't count on it. The odds of lightning bolts hitting both pupils during a freak earthquake at 6.66 pm are higher, according to British bookies Ladbrokes.

Forget about feeling suffused with an all-embracing love of humanity, especially when the shoe-shiner who lurks outside your office flicks polish on your loafers, then offers to remove it for 20 yuan.

Even when locals try to get in on the act, Christmas in China doesn't feel quite right. One child told me she was going to take her grandparents to eat spicy hot pot.