Is self-harm the answer?

Is it bad to consider stabbing your own arm so you can have an excuse to leave work? (You'd think self-harm wouldn't be necessary, considering my track record of personal injury... but for some strange reason I have been injury free for a couple years - crap I just jinxed myself - expect to see my in a sling or cast within a month). Anyway, I have been pondering the self-harm thought for nearly four days now. I refuse to take annual leave and go home - especially when I have nothing fun planned. Instead I choose to take a mental health afternoon..... seriously, my mental health is at risk due to the mindless hours of sitting at my desk stalking blogs (don't judge you all do it!)